OpenSprinkler not only receives regular software updates, but the hardware—the physical device itself—is also continuously improved. The last update was to version 3.3 in 2023, and now there’s another leap to version 3.4. The new OpenSprinkler 3.4 is immediately recognizable by its slightly altered appearance. It looks a bit more square, is slightly narrower, but taller and flatter than the old model. Dimensions in detail:

• OpenSprinkler 3.4: Length 125 mm, Width 79 mm, Height 25 mm
• OpenSprinkler 3.3: Length 140 mm, Width 56 mm, Height 33 mm

The new model is on the left, the old model on the right.

Technical changes in detail:

2 new sensor inputs

The OpenSprinkler 3.4 now has 4 sensor inputs instead of the previous 2. This allows for the connection of more sensors. However, a software update is still required so that the software offers the two additional ports for selection; this should be released soon.

Now 4 instead of 2 sensor inputs (SN1 to SN4)

Connection option for Ethernet module

For OpenSprinkler version 3.0 and later, a wired LAN connection was not originally planned, based on the assumption that a web connection could be made using the integrated Wi-Fi functionality. However, it was underestimated that many users still prefer a reliable wired connection.

Therefore, an improvised Ethernet port was added inside the device with OpenSprinkler 3.3, which could be used with a little tinkering. OpenSprinkler 3.4 now makes this significantly easier by providing a user-friendly Ethernet connection via a ribbon cable port on the right side of the device.

It would be even better, of course, to install an Ethernet port there instead of the ribbon cable port. As it stands, the additional Ethernet module shown below is still required, costing approximately $25.

Switching from a two-layer to a single-layer circuit design

Not something that directly benefits the user, but interesting background information: OpenSprinkler previously used a two-layer circuit design, consisting of an upper logic board and a lower driver board.

This was originally intended to allow for interchangeable driver boards (AC, DC, and Latch) to connect different solenoid valve types via the same logic board. Using only one board now significantly simplifies assembly, enabling more efficient and time-saving manufacturing.

Power Supply Connection

The power supply is no longer connected directly via the cable wires, but rather via a more user-friendly barrel connector. This eliminates the need to strip the wires; instead, a standard, readily available connector can be used.

New Barrel Connector

USB 3.0 Power Connection on the DC Model

The OpenSprinkler 3.4 continues to be available as an AC (alternating current) and DC (direct current) model. The Latch model, previously offered as a third option, is no longer available for version 3.4. This latch model is required for use with the typical 9V solenoid valves for battery-operated irrigation controllers, which are often marked with the word “Latch.” The latch model from its predecessor, OpenSprinkler 3.3, is still available for this purpose.

At first glance, the DC model appears almost identical to the AC model, with the key difference being that it now features a modern USB 3.0 input instead of a barrel connector for power.

On the left, the DC model with the USB 3.0 connection; on the right, the AC model with the barrel connector.

OpenSprinkler 3.4 DC with power plug attached.

This connection eliminates the need for specific power supplies; the controller can simply be plugged into a wall outlet using the standard USB 3.0 connector. Therefore, the OpenSprinkler DC model is generally preferable to the AC model. The DC model can switch both standard 24V AC solenoid valves and non-holding DC solenoid valves, and it also operates more energy-efficiently than its AC counterpart.

The AC model, on the other hand, can only switch 24V AC solenoid valves. This model should only be used if you intend to use the computer to control a pump start relay, as the DC version is not compatible with all pump start relays available on the market.

Conclusion

OpenSprinkler 3.4 brings some excellent improvements! Particularly noteworthy are the two additional sensor inputs, the improved Ethernet connectivity, and especially the simpler power supply with a barrel connector on the AC model and, even more importantly, the new USB 3.0 port on the DC model.

If two sensor inputs are sufficient for your needs and you don’t plan to connect your computer directly to the LAN, then the predecessor model 3.3, which is still available in some places, represents a worthwhile and affordable alternative due to the significant price reduction now offered.

Note: Readers of this blog are offered a 10% discount by the OpenSprinkler Shop when purchasing an OpenSprinkler or OpenSprinkler Pi. Use the coupon code OSPOWER15YR when ordering!

Der Beitrag New OpenSprinkler 3.4 erschien zuerst auf Irrigation Blog for Do-it-yourselfer.

OpenSprinkler is a web-based, open-source irrigation controller. Both the software code and the hardware schematics are freely available to everyone and can be used for personal projects and further development. This article explains the advantages of this open-source nature, the different versions of the controller currently available, and which version is best suited for different users.

To understand exactly what OpenSprinkler is, it’s helpful to take a brief look at the product’s history:

OpenSprinkler History

Unlike other irrigation controllers on the market, OpenSprinkler wasn’t developed by a professional irrigation or electronics company. Instead, it resulted from a private initiative by Ray Wang, an IT professor at the University of Massachusetts Amherst.

In 2010, he installed an irrigation system in his own garden and began searching for a suitable controller. The products available on the market reminded him of the long-gone 1980s in terms of functionality and design, offering very limited features and no web connectivity. So Wang took matters into his own hands and, within a few weeks, built his own irrigation controller with web connectivity and more functionality, presenting this prototype on his personal blog. The prototype and the idea behind it were very well received and marked the beginning of OpenSprinkler.

Ray founded a company with commercial intentions to handle the production, marketing, and distribution of the product. At the same time, he committed himself to the open-source philosophy, making the source code of the software and the computer’s blueprints publicly available. This allows third parties to fully understand how the product works and, consequently, to improve it independently. Anyone with ambitions in this direction can therefore build directly upon the current state of development and doesn’t have to start from scratch.

The first OpenSprinkler 1.0 was released in 2011. Initially, it was a do-it-yourself kit that allowed users to assemble the finished sprinkler themselves within a few hours. The irrigation controller was structurally limited to the essentials. It consisted of the actual computer, a simple ATmega328 microcontroller, an Ethernet controller for connecting to a LAN network, an 8-channel relay for switching up to eight 24V solenoid valves, and a simple cover to protect the components.

Do-it-yourself kit for OpenSprinkler 1.1

And this is what the fully assembled irrigation computer looked like.

Visually, it didn’t have much in common with irrigation controllers from other manufacturers, but it offered significant advantages: First, programming and operation were possible via a web interface, making it convenient to use a PC or laptop’s web browser, unlike other manufacturers’ controllers, which only allowed direct access. Second, with some effort and existing programming knowledge, the irrigation programming could be tailored to individual needs (the software is maintained on the Arduino platform, using the C/C++ programming language), and the web connection allowed for the integration of external data, such as weather information, for irrigation.

The observation that some users were using OpenSprinkler in combination with a Raspberry Pi computer led to the additional development of OpenSprinkler Pi in 2013. This is not a complete irrigation controller, but rather a sprinkler expansion board for Raspberry Pi users. It can be connected to the computer, thus adding sprinkler functionality.

In 2013, a dedicated OpenSprinkler app was developed, allowing for convenient operation of the software via mobile phone.

In 2016, the product range was expanded to include OpenSprinkler Bee, a small irrigation controller for battery-operated 9V solenoid valves that can control up to three valves.

Over the years, the software has been continuously developed, and new hardware versions have been released. A description of the currently available products, including an assessment of who I believe they are suitable for, can be found below:

OpenSprinkler Irrigation Controller

The OpenSprinkler irrigation controller is currently available in version 3.4. It is now a fully assembled irrigation controller; no further assembly is required. The controller is ready to use immediately and is no different from irrigation controllers from other manufacturers in this respect.

The controller can be ordered in three different power supply options:

• Powered by a 24V AC adapter
• Powered by a 7.5V DC adapter
• Powered by a 7.5V DC adapter for self-holding “latch” valves (7.5V DC Latch), only available in version 3.3

If you are using self-holding DC latch solenoid valves (these are the typical 9V solenoid valves for battery-operated irrigation controllers and are usually marked with “Latch”), then the third option is mandatory, as only this option can control such latch valves. If not, then the second option, 7.5V DC, is usually preferable, as it can switch both standard 24V AC solenoid valves and non-holding DC solenoid valves. The first option should be used if you intend to use the computer to control a pump start relay, as the second option is not compatible with all pump start relays available on the market.

In addition, an optional module for an Ethernet LAN output can be ordered alongside the Wi-Fi connection.

Below is an overview of the OpenSprinkler performance data.

	OpenSprinkler 3.4
Model variants	2 variants: 24V AC (for 24V AC valves), 7.5V DC (for 24V AC valves and 7.5V to 12V DC valves), only available for OpenSprinkler 3.3: 7.5V DC Latch (for 7.5V to 12V DC Latch valves)
Number of controllable solenoid valves	8 (expandable by 16 additional zones with an additional module, a maximum of 4 additional modules can be connected, the maximum possible number of zones is therefore 72)
Can it be used with 24-volt or 9-volt solenoid valves?	Depending on the model variant
Programming options	Up to 40 programs can be configured to control the defined zones; each program can have up to 4 start times per day. A special feature of OpenSprinkler is the ability to start multiple zones simultaneously.
Irrigation duration	1 second to 1,080 minutes
Global increase/reduction of irrigation duration	1 to 250%
Connectable sensors	Four sensor ports are available, allowing the connection of a rain sensor, soil moisture sensor, flow sensor, programmable switch, or any other sensor operating on a normally open or normally closed principle. The specific sensor and its operating characteristics are defined in the software.
Connection for master valve/pump start circuit?	There is no dedicated connection, but one of the eight existing zone connections in the software can be defined as the connection for the master valve. Similarly, a second connection can also be defined as master valve 2.
Is direct control via computer possible?	Only to a very limited extent (the small display and the 3 selection buttons only show some basic information such as the time, zone status and rain status, and you can start programs manually)
Power/Battery	Power connection via externally mounted 24 Volt AC or 7.5 Volt DC transformer (depending on model)
Indoor/Outdoor	Indoor use (for weatherproof outdoor use, a separate IP-65 enclosure can be purchased)
WiFi?	Yes (optional additional LAN connection via add-on module also possible)
The app runs on	Apple iOS devices, Google Android devices
Access via web browser possible?	Yes
Use of local weather data?	Yes
Price	$140 or $183 with an additional LAN port

Who would benefit from an OpenSprinkler irrigation controller?

Unlike in 2011, when the first OpenSprinkler was launched, there are now numerous smart irrigation controllers on the market that can be controlled via the web.

In my opinion, the most sophisticated systems currently available are Hunter Hydrawise and LinkTap. Orbit’s B-hyve also offers a quite powerful solution with a very good price-performance ratio. All three systems are characterized by their ability to provide highly customized, weather-data-based automated irrigation. If you are primarily looking for an irrigation controller that can be remotely controlled from anywhere in the world via an app, but without sophisticated weather-dependent control options, then the RainPoint computers, the Rain Bird Smart Watering System, or the Smart System from the German manufacturer Gardena are further alternatives.

Therefore, OpenSprinkler can no longer rely on web control as a key selling point. However, it does differ from other providers in several aspects that may make it interesting for some users:

Der Beitrag What are OpenSprinkler and OpenSprinkler Pi, and who do they make sense for? erschien zuerst auf Irrigation Blog for Do-it-yourselfer.

Several years ago, I reviewed the predecessor to the LinkTap G2S, the LinkTap G2, on my blog, and it performed quite well in my test. Now it was high time to take a closer look at the current LinkTap model. In this post, I’ll examine the LinkTap’s functionalities, how it has improved compared to its predecessor, and how it compares to competing irrigation controllers.

Like all LinkTap irrigation controllers, the LinkTap G2S requires an additional gateway to operate. And, unlike Wi-Fi, it uses the more reliable Zigbee protocol for wireless communication between the gateway and the irrigation controller.

The G2S’s Place in the LinkTap Product Range

The LinkTap G2S, along with the G1S, is the smallest LinkTap irrigation controller, both have one output. What distinguishes the G2S from the G1S? The G2S is essentially a G1S with the addition of a water flow sensor and a tilt sensor. These two sensors allow you to monitor the proper functioning of your irrigation system: The tilt sensor detects and automatically alerts you if the controller falls from its designated position during operation. The even more important water flow sensor triggers an alarm if water flow is detected when no irrigation is running or if other unusual behavior is observed.

With a current price difference of only about $25, I would definitely recommend the G2S due to the numerous functionalities of the water flow sensor (more on this later in the article)!

What other alternatives does LinkTap offer to the G2S, and how do they differ? The other LinkTap models essentially have the same functionality and all use the same app; the main difference lies in the number of outputs.

The LinkTap D1 and the LinkTap T1 both have two outputs. The T1 is designed for harsher weather conditions (wetlands, coastal areas, or flood-prone areas) compared to the D1. The control unit and valve unit are divided into two separate devices. The batteries and most of the electronics are housed in the Valve Linker, which has two outlets and can be mounted separately from the valve unit in a more moisture-protected location. Both controllers are priced similarly.

The LinkTap Q1 is the largest LinkTap model with four outlets.

The G1S, G2S, D1, T1, and Q1 are irrigation controllers through which the water flows directly. LinkTap also offers the ValveLinker, a second type of irrigation controller that does not come into direct contact with water but serves as a control center for external solenoid valves. It is available in three models for controlling one, two, or four solenoid valves.

Tabular comparison of LinkTap models:

Computer

LinkTap G1S

LinkTap G2S

LinkTap D1

LinkTap T1

LinkTap Q1

LinkTap V1 ("Valve Linker")

Zones

1

1

2

2

4

1, 2 or 4 (depending on the variant)

Integrated/ Connectable Water Flow Sensor?

Rain sensor connectable?

Soil moisture sensor connectable?

Manual watering at the touch of a button?

Batteries

4 x AA batteries

4 x AA batteries

4 x AA batteries

2 x 9 V block batteries

2 x 9 V block batteries

2 x 9 V block batteries

Variants

Z1 (1 zone), Z2 (2 zones), Z4 (4 zones)

Price

$85.00

$119.00

$149.00

$189.00

$269.00

$159.00

Computer

LinkTap G1S

Zones

1

Integrated/ Connectable Water Flow Sensor?

Rain sensor connectable?

Soil moisture sensor connectable?

Manual watering at the touch of a button?

Batteries

4 x AA batteries

Variants

Price

$85.00

Computer

LinkTap G2S

Zones

1

Integrated/ Connectable Water Flow Sensor?

Rain sensor connectable?

Soil moisture sensor connectable?

Manual watering at the touch of a button?

Batteries

4 x AA batteries

Variants

Price

$119.00

Computer

LinkTap D1

Zones

2

Integrated/ Connectable Water Flow Sensor?

Rain sensor connectable?

Soil moisture sensor connectable?

Manual watering at the touch of a button?

Batteries

4 x AA batteries

Variants

Price

$149.00

Computer

LinkTap T1

Zones

2

Integrated/ Connectable Water Flow Sensor?

Rain sensor connectable?

Soil moisture sensor connectable?

Manual watering at the touch of a button?

Batteries

2 x 9 V block batteries

Variants

Price

$189.00

Computer

LinkTap Q1

Zones

4

Integrated/ Connectable Water Flow Sensor?

Rain sensor connectable?

Soil moisture sensor connectable?

Manual watering at the touch of a button?

Batteries

2 x 9 V block batteries

Variants

Price

$269.00

Computer

LinkTap V1 ("Valve Linker")

Zones

1, 2 or 4 (depending on the variant)

Integrated/ Connectable Water Flow Sensor?

Rain sensor connectable?

Soil moisture sensor connectable?

Manual watering at the touch of a button?

Batteries

2 x 9 V block batteries

Variants

Z1 (1 zone), Z2 (2 zones), Z4 (4 zones)

Price

$159.00

Product Scope

The LinkTap G2S comes in a compact box. Since I already own the gateway from previous tests, I ordered a set without it. If you don’t already have a LinkTap device, you’ll need to opt for a set with the gateway! This costs approximately $30 more.

The LinkTap G2S in its original packaging

The LinkTap G2S package includes the irrigation controller, the water flow sensor, a warranty card, a quick start guide, a 1/2-inch tap connector, a spare sealing ring, and a screwdriver for opening the battery compartment.

Also included is a threaded adapter that allows you to optionally reduce the irrigation controller’s inlet to 1/2 inch. A second adapter, which reduces the inlet from 1 inch to 3/4 inch, is already pre-installed. This allows you to screw the controller onto a 1-inch, 3/4-inch, or 1/2-inch threaded connection.

Batteries are not included. My package without the gateway includes a quick start guide; LinkTap assumes that existing users don’t need another full manual, which certainly makes sense from an environmental perspective. The complete G2S kit, including the gateway, in contrast includes a full user manual. All necessary installation steps and information about functionalities can also be found after downloading the LinkTap app, on the LinkTap website, or here on the blog.

Included in the package

Setup

As with virtually all smart irrigation controllers these days, initial setup is straightforward and takes approximately 10 to 15 minutes. To begin, download the LinkTap app for Android phones via Google Play and for Apple phones via the App Store.

The app provides step-by-step instructions for setup. First, install the gateway, followed by the irrigation controller. For installation and ongoing operation, the gateway must be connected to your internet router via an Ethernet cable. If your router doesn’t have a LAN port or if it’s already in use by another device, you can use a Wi-Fi repeater with a built-in Ethernet port (Amazon link), as shown in the following image. These can be purchased for around $15.

Update: LinkTap has announced that future models will offer both connectivity options: Ethernet and Wi-Fi (2.4 GHz and 5 GHz). This is expected to be available for models from around 2026 onwards.

To add the gateway to the app, simply connect it to power and your LAN. Then, scan the number printed on the back of the gateway with your phone’s camera or enter it manually. The gateway will then be detected and ready to use.

The same process is then repeated for the irrigation controller: Enter the number on the back of the controller into the app. Next, insert four batteries into the irrigation controller and remember to switch it on using the small switch on the bottom. The irrigation controller will now also be detected and ready for use.

Hardware

Before I discuss the computer’s software, a few words about the hardware, i.e., the device itself. There are basically two types of irrigation controllers: In the first type, the solenoid valve, which opens and closes with each watering cycle, is integrated directly into the controller. This means the controller comes into direct contact with water. In the second type, the irrigation controller is purely a control unit that operates externally located solenoid valves; there is no direct contact with water.

The LinkTap G2S is a controller of the first type, through which the water flows directly. This type of irrigation controller has significantly higher manufacturing requirements than the second type. Due to constant contact with water and the typically exposed, not particularly weatherproof installation, many such controllers tend to leak after one or two seasons or to malfunction, with the integrated solenoid valve no longer opening and closing properly.

The market of such WiFi faucet controllers is relatively limited, as some major manufacturers like Rain Bird and Hunter don’t offer them, focusing entirely on the second type of irrigation timer. The LinkTap G2S competes in this segment of single-outlet devices with the Gardena Smart Water Control, the Orbit B-hyve Smart Faucet Timer, the RainPoint HTV145FRF, the Eve Aqua, and a handful of no-name irrigation timers.

Of all these alternatives, LinkTap offers the highest-quality hardware in my opinion!

Housing

The housing of the G2S

The housing of the G2S, like all LinkTap models, is made of very sturdy, hard plastic. At first touch, it almost feels like metal because it’s so solid. The irrigation controller feels very high-quality overall; nothing wobbles, the connections were watertight in my tests right away, even without additional sealant, and based on my experience, the controller still works perfectly after two or three seasons.

Unfortunately, this isn’t always the case. I’ve had many unpleasant surprises in this regard during my testing with other brands. On the one hand, I’ve encountered devices that are cheaply made from the outset and feel so flimsy and cheap that you’d rather not even touch them for fear of breaking something or not being able to properly close a battery compartment once opened.

On the other hand, I’ve encountered devices that initially look and function quite well, but then, in the second or third season, leak due to brittle material or the solenoid valve no longer opens and closes properly. This is tantamount to total failure and is particularly frustrating with a relatively expensive Wi-Fi device.

Finally, some manufacturers have very lax quality control, so I’ve already encountered several devices I bought for testing that were already malfunctioning upon delivery and had to be replaced.

Therefore, my urgent advice is: When it comes to this type of irrigation controller that screws directly onto the tap, pay particular attention to proper manufacturing quality! You ultimately save nothing if you have to replace a supposedly “cheap purchase” after only two or three seasons!

LinkTap stands out positively in this regard: The products are robust and durable and appear to undergo thorough final inspection. So far, I haven’t encountered a single LinkTap product with obvious defects in my tests. This is also confirmed by the very good reviews on Amazon (4.7 out of 5 stars). I also find it worth mentioning that LinkTap actively focuses on sustainability and provides instructions on its website for repairing minor defects yourself. LinkTap also offers many repair parts free of charge, requiring only the customer to cover shipping costs.

Water Flow Sensor

A special feature is the water flow sensor, which LinkTap includes in all its computer models except the G1S, or at least offers the option to add one. This provides a significant advantage in monitoring and ensuring irrigation, a point that is often overlooked when purchasing an irrigation controller.

The water flow sensor is simply screwed onto the bottom of the outlet and the cable is plugged into the sensor input

In the event of a valve not closing properly, water can leak uncontrollably over a long period and cause damage. Less dramatic, but still annoying, is the case if a valve doesn’t open properly and the plants in your garden dry out. Both risks can be significantly reduced with a water flow sensor. This sensor detects unwanted or unusual behavior and automatically sends a notification when it occurs, allowing you to react promptly.

Note: Even though the more affordable model, the LinkTap G1S, looks almost identical to the LinkTap G2S, it cannot be retrofitted with a water flow sensor because the necessary input is missing. Therefore, if you plan to use such a sensor, you must choose the G2S from the start!

At present, the G2S does not support the Advanced Flow Monitoring feature, a very clever monitoring option for the irrigation controller in conjunction with a flow switch, water level switch, or float valve. This feature is currently only available with the LinkTap models T1, Q1, and ValveLinker.

It’s important to be aware that using a water flow sensor always reduces water pressure slightly. You can think of it like a small turbine that’s turned by the water, thus measuring the flow rate. This isn’t a problem if the water source is adequately sized, but it can become an issue if the irrigation system is already tightly calculated and the sprinklers then no longer reach their intended throw distance. If necessary, the G2S can also be operated without the water flow sensor. Simply unscrew it and connect it directly to the threaded outlet.

Micro Flow Meter FM20-S

LinkTap offers a second water flow sensor, the Micro Flow Meter, as an alternative to the water flow sensor included in the kit. This second sensor is suitable for very low flow rates, such as those found in micro-irrigation solutions. Standard water flow sensors are incapable of handling such small volumes. The water flow sensor included in the kit is designed for flow rates of at least 30 gallons (120 liters) up to a maximum of 800 gallons (3.000 liters) per hour. The Micro Flow Meter, on the other hand, is suitable for very low flow rates, from 3 gallons (12 liters) per hour up to a maximum of 80 gallons (300 liters) per hour. It costs $20.

Alternative for micro-irrigation systems with very low water flow rates: LinkTap FM20-S Micro Flow Meter

Manually Starting an Irrigation Cycle

From my own experience, this is quite important: The G2S has a blue button on the front for starting an irrigation cycle directly on the computer. Nothing is more annoying than standing in front of the irrigation controller wanting to start a quick watering cycle, only to find you can’t because you don’t have your mobile phone handy.

This button is a new addition compared to the previous G2 model. Pressing the button starts the irrigation cycle. By default, it runs for 30 minutes, but can be ended prematurely at any time by pressing the button again. The 30-minute duration is also adjustable in the app; it can be set to any value between 1 and 1439 minutes.

On/Off Switch

A small detail, but still worth mentioning: The LinkTap controllers are currently the only irrigation controllers I know of that have their own on/off switch. This can be quite practical for switching off the irrigation controller if you won’t be using it for an extended period. This saves you the trouble of removing the batteries.

Inlet and Outlet

Two adapters are included for the inlet, allowing the irrigation controller to be used with 1-inch, 3/4-inch, and 1/2-inch faucets. A 1/2-inch tap connector is included for the outlet. If using the controller for an irrigation system, this connector should definitely be replaced with a 3/4-inch tap connector to avoid unnecessary pressure loss.

Wireless Connection

The high-quality wireless connection is a key feature. LinkTap deliberately uses the Zigbee protocol for communication between the gateway and the irrigation controller, as it offers a more stable and longer range compared to Wi-Fi. This can be a significant advantage if there are obstacles that are difficult for the wireless signal to overcome or if the two devices are far apart. In my tests, the wireless connection was sufficient for distances of up to 100 feet (30 meters) between the gateway and the irrigation controller; beyond 130 feet (40 meters), the connection failed.

For particularly large gardens or challenging locations, LinkTap offers the option of integrating a signal repeater. The LinkTap Extender costs $40, operates wirelessly, and is weatherproof. It can be positioned between the gateway and the irrigation controller, creating a mesh network between the components. For particularly long distances, multiple extenders can be connected in series. The extender can be powered by battery or cable. It can also be connected to a small solar panel.

Additional Sensors

Currently, neither a rain sensor nor a soil moisture sensor can be used with LinkTap devices. Due to the weather control enabled by the software, there is no real need for a rain sensor, but a soil moisture sensor can be quite useful in practice in addition to weather control. According to LinkTap, connecting such a sensor without a physical output will be possible via the software in the near future.

Pressure Loss

During a bucket test, I also specifically examined the pressure loss associated with using the G2S. It’s important to be aware that using an irrigation controller always results in a certain pressure loss compared to directly connecting the pipeline or hose to the water source.

First, I measured the water flow per hour at the outdoor tap where the test was conducted without the irrigation controller. Result: 550 gallons (2.100 liters) per hour.

Then I repeated the bucket test with the G2S irrigation controller. The water flow rate in the bucket test is reduced to approximately 400 gallons (1.500 liters) per hour when using the G2S. Out of curiosity, I also repeated the test without the water flow sensor attached, which resulted in a flow rate of about 420 gallons (1.600 liters) per hour – not a significant difference. With these figures, the G2S performs roughly on par with competitor products, although in my opinion, all of them still have room for improvement, namely by designing irrigation controllers with fewer bottlenecks. Only the Gardena Smart Water Control has a slightly better design in terms of pressure loss.

Software

This is the area where LinkTap has made the most progress since testing its predecessor. In my comparison of WiFi apps from the leading irrigation controller manufacturers, LinkTap is currently in second place and is hot on the heels of Hydrawise, the current top-performing software.

The weather control function is very user-friendly and includes all the essential features. While not quite as detailed as the Hydrawise system, it’s very practical in my opinion.Furthermore, the LinkTap app offers the best functionality when used with a water flow sensor and includes features like Smart Anti-Freeze Protection, which are not found in any other system.

And very importantly: LinkTap is currently the most innovative system on the market, with continuous software development. Most recently, enhanced flow monitoring and intelligent frost protection were added, and according to the Australian LinkTap developers, further software enhancements are planned. For example, it should be possible to use your own weather station in the future. You automatically benefit from these future expansions through the free updates available via the app.

In the following article, I have examined the LinkTap software in great detail and describe all its functionalities: Complete description of the LinkTap app’s features. The following table summarizes the key features of the software:

Computer

LinkTap G2S

Software system

LinkTap

App runs on

Apple iOS devices, Google Android devices

Accessible via web browser?

Setup wizard for initial setup?start circuit?

Type of programming

On a zone basis

Start times

100

Watering duration

3 seconds to 24 hours

Types of irrigation

Interval mode, 7-day mode, odd-even mode, month mode or calendar mode

Definition of irrigation templates?

Local access without an internet connection?

No, however, Home Assistant integration is supported, allowing local access without a web connection.

Give access to other users?

Assigning different user authorizations?

Additional functions for contractors?

Yes, professionals have the option of creating an user account on behalf of the client and setting it up and testing it for them before handover to the client.

Warning notifications?

Irrigation calendar?

Reports on irrigation, water consumption, weather, ...?

Connection of a flow meter?

Water flow meter is permanently integrated into the computer!

Computer

LinkTap G2S

Software system

LinkTap

App runs on

Apple iOS devices, Google Android devices

Accessible via web browser?

Setup wizard for initial setup?start circuit?

Type of programming

On a zone basis

Start times

100

Watering duration

3 seconds to 24 hours

Types of irrigation

Interval mode, 7-day mode, odd-even mode, month mode or calendar mode

Definition of irrigation templates?

Local access without an internet connection?

No, however, Home Assistant integration is supported, allowing local access without a web connection.

Give access to other users?

Assigning different user authorizations?

Additional functions for contractors?

Yes, professionals have the option of creating an user account on behalf of the client and setting it up and testing it for them before handover to the client.

Warning notifications?

Irrigation calendar?

Reports on irrigation, water consumption, weather, ...?

Connection of a flow meter?

Water flow meter is permanently integrated into the computer!

Continuation

Computer

LinkTap G2S

Define irrigation triggers?

Rules can be defined regarding rainfall and temperature, which can suspend irrigation runs or adjust the duration of irrigation

Using local weather data?

Weather station selectable?

Updating weather data

Before starting an irrigation run, storage for 6 hours

Integration of your own weather station possible?

Currently no (but should be possible in the future)

Seasonal adjustment definable per month?

No - Only possible to a limited extent

Suspend watering x days?

Cycle and soak phases?

Lawn growth program?

Start watering run manually?

Define a sensor yourself?

Master valve usable?

Valve delays definable?

Voice control with

Amazon Alexa, Google Assistant possible via IFTTT

Ongoing costs?

None

Computer

LinkTap G2S

Define irrigation triggers?

Rules can be defined regarding rainfall and temperature, which can suspend irrigation runs or adjust the duration of irrigation

Using local weather data?

Weather station selectable?

Updating weather data

Before starting an irrigation run, storage for 6 hours

Integration of your own weather station possible?

Currently no (but should be possible in the future)

Seasonal adjustment definable per month?

No - Only possible to a limited extent

Suspend watering x days?

Cycle and soak phases?

Lawn growth program?

Start watering run manually?

Define a sensor yourself?

Master valve usable?

Valve delays definable?

Voice control with

Amazon Alexa, Google Assistant possible via IFTTT

Ongoing costs?

None

Here is some additional information on a few selected points:

Irrigation Types

When creating an irrigation schedule, you can choose from 5 different types: Interval mode, 7-day mode, Odd/Even mode, Month mode, or Calendar mode. This should cover virtually all conceivable scenarios. The Calendar mode offers the greatest possible flexibility.

Creating Irrigation Templates

While you cannot explicitly create templates, any irrigation schedule you create can be used as a template for other schedules, which essentially amounts to the same thing.

Granting Access to Other Users

It is possible to grant access to the app to other people. To do this, you can send an email invitation from within the app. You will be notified if the invitee accepts the invitation. Guest access, once granted, can be managed and revoked via the app.

Alert Notifications

Comprehensive alert notifications can be activated for up to nine events, as well as for additional events related to water flow. Notifications are received via push notification on your mobile phone and via email. A special feature: You can register up to two additional email addresses to which the alert emails will be sent.

Use of Weather Data

Weather data is obtained from the Apple WeatherKit service for the user’s local location. A specific weather station cannot be selected. According to LinkTap, the option to use your own weather station will be available in the future. Currently, this is not possible, unlike with Orbit B-hyve, Opensprinkler, and Hunter Hydrawise (for an additional fee).

Suspend Irrigation

Irrigation can be suspended for any duration between 0.1 and 240 hours, or paused indefinitely (with common presets such as 6, 12, 24, 48, and 72 hours).

Set pause time

Use a Master Valve

LiLinkTap is the only irrigation controller of this type that I know of that allows the use of a master valve. For this purpose, a second LinkTap controller can be defined as the master valve.

Price and Availability

The complete G2S set, including the gateway, costs approximately $120 to $140. Without the gateway, it’s about $30 less.

As far as I know, the computer is only available online. Amazon offers a wide selection, while the complete range is available directly from the LinkTap online shop.

Note: As a reader of this blog, you can use a 5% discount coupon when shopping in the LinkTap online shop. Coupon code: LINKTAP-BSB! Like Amazon, LinkTap offers free shipping on all orders.

Conclusion and Recommendation

The LinkTap G2S has improved significantly compared to the LinkTap G2, which I tested in 2020! The hardware was already very good back then and has been slightly enhanced with a practical button for manual watering. In terms of hardware, LinkTap is currently the leader in faucet control water timers, in my opinion. The quality and durability of the hardware are extremely important for this type of irrigation controller, as they are subjected to heavy use and therefore sometimes break down very quickly.

A very good feature is the integrated water flow sensor. On the one hand, this allows you to keep a close eye on water consumption. Even more importantly, the sensor provides immediate notification of problems such as a valve that isn’t opening or closing properly, or a leak. This allows you to react immediately before any damage occurs.

The LinkTap software has made a significant leap forward, now offering even more sophisticated weather control based on both rainfall and temperature. Regarding rainfall, it can take into account both past and expected precipitation. Regarding temperature, the amount of water applied can be adjusted if the temperature exceeds a certain level when irrigation starts. The time period to be considered, as well as the amount of rainfall, watering volume, and temperature, can be freely entered. This works very well; only Hydrawise offers even more detailed weather control.

Furthermore, the LinkTap software includes several sophisticated features, such as an automatic temperature warning that uses a built-in temperature sensor to alert you to the risk of frost. Above all, LinkTap is currently the most innovative company among all manufacturers, continuously developing its software and gradually incorporating additional features requested by users.

LinkTap’s devices are generally positioned in the higher price range, and the LinkTap G2S, at $120 to $140, is no exception. However, compared to the overpriced Gardena Smart Water Control, the G2S is still relatively inexpensive. The Eve Aqua, which only works with Apple Home, is priced similarly, while the Orbit B-hyve Smart Faucet Timer and the RainPoint HTV145FRF, at around $80, are significantly cheaper, as are some generic, unbranded devices.

Despite its robust and high-quality hardware, which promises a longer lifespan, and especially its now-best software among faucet control water timers, the LinkTap G2S is my top recommendation!

In direct comparison to its competitors: The Gardena Smart Water Control is expensive and has very weak software. I would only consider it if you already own other smart Gardena devices, and even then, probably not.

The Eve Aqua costs about the same, but is essentially just a smart plug with much lower build quality than the G2S. It lacks a water flow sensor, only works with Apple Home, and has significantly reduced software with far fewer features.

The Orbit B-hyve Smart Faucet Timer is considerably cheaper and also includes a water flow sensor. Its software isn’t bad, but in my opinion, it’s somewhat inferior to the LinkTap software. What I dislike about Orbit is my experience with the build quality and durability of their devices. The price difference makes it worth considering, but you could also end up disappointed and annoyed if you have to replace the computer after only a short time.

Of the Chinese RainPoint computers, I’ve only tested the RainPoint models with two outputs so far. The hardware looks decent at first glance, but I lack the long-term experience to comment on its durability. The RainPoint software is at least two classes below LinkTap’s. However, if the software isn’t a priority and you primarily want to control the computer wirelessly and the low price is your main concern, it’s a worthwhile alternative.

The cheapest no-name water timer with WiFi (Amazon link) currently start at around $30. These are very basic devices whose software is essentially limited to remotely switching the controller on and off. These manufacturers have little to no experience with garden irrigation, and you shouldn’t expect much in terms of hardware quality and durability.

Final conclusion: The LinkTap G2S is currently the top choice among tap water timers due to its superior hardware and software! While the G2S can’t compete with the cheapest alternatives on price, I believe the higher price is justified by what it offers.

Der Beitrag LinkTap G2S review erschien zuerst auf Irrigation Blog for Do-it-yourselfer.

All the methods described use liquid fertilizer, which is added to the watering can. These liquid fertilizers are generally water-soluble and can therefore be mixed with water. Some systems also allow the use of fertilizer granules, which are dissolved in the water before watering. Compared to fertilizing with conventional fertilizer, fertilizing with liquid fertilizer offers the following advantages:

• Less time required
• Relatively user-friendly and easy to apply
• Effective and consistent results
• In dry weather, the fertilizer is absorbed into the soil immediately
• It works very quickly (however, the effect is shorter-lasting than with solid fertilizer, so more frequent fertilization is necessary)

To prevent the risk of the fertilizer-mixed water flowing back towards the water source, a check valve should be installed between the water source and the fertilization system. If using drinking water directly from the drinking water system, the stricter regulations regarding drinking water protection must be observed.

Three Types of Systems

Regarding the basic operating principle for fertilizer application, three types of systems can be distinguished:

• Vacuum-based systems
• Pump-based systems
• Very simple systems where the fertilizer is simply flushed from the fertilizer container by means of a water supply

The systems in the first group deliberately create a vacuum to “suck” the fertilizer from the fertilizer container into the irrigation circuit, while those in the second group accomplish this with their own pump. The vacuum-based systems are usually less expensive to purchase and generally also relatively easy to use. The systems in the last group are even simpler, where water is simply added to the fertilizer container and flushed out again as a water-fertilizer mixture. These are specifically aimed at private end users with a focus on ease of use and are not suitable for professional applications.

I will present the different options available on the market below, starting with the simplest and progressing to more complex systems. First, three solutions for manual application, apart from automatic garden irrigation.

Liquid fertilizer container with spray attachment

Liquid fertilizer bottles and canisters (Amazon Link) are available on the market, to which a standard 1/2-inch hose can be directly connected. The fertilizer is automatically added to the watering can in a preset ratio and applied using the spray device integrated into the container. If a water connection and hose are already available, this option can be implemented with zero investment costs.

Special Garden Hose Nozzles with Fertilizer Dispenser

Fertilizing with a special garden hose nozzle equipped with a fertilizer reservoir, which can be refilled, works similarly to the previous method, but even more sophisticated and refined. You connect the hose nozzle to the garden hose and the desired dosage can be adjusted on the nozzle itself; watering is otherwise done as normal. Alternatively, such a garden hose nozzle (Amazon Link) can also be used with cleaning agents for car washing. They cost approximately $15 to $30.

Pump sprayers

These offer a possible alternative to using liquid fertilizer when a hose connection is unavailable. Pump sprayers (Amazon Link) are typically available in 1-gallon or 2-gallon capacities.. How they work: Water and fertilizer are added to the spray bottle, the bottle is sealed, and the pressure inside is increased by pumping several times. This is achieved using a piston with a handle inside the bottle. This piston functions like a piston pump. Because it is relatively large, a small amount of air is pumped into the bottle with just a few pumps, quickly building up the required pressure.

A spray lance is connected to the spray bottle via a hose. Pressing a button releases the pressurized liquid.

These pump sprayers can also be used to apply weed killer or cleaning foam, in addition to fertilizer.

Integrating Fertilization into an Automatic Irrigation System

The fertilization systems presented below are designed for permanent integration into an irrigation system, allowing fertilization to be carried out automatically during watering without any further manual intervention.

Fertilizer Dispenser

These are self-contained systems for private use that can be used immediately in the irrigation system without additional components. Due to their limited capacity and maximum pressure, they are primarily suitable for micro-irrigation. They consist of a fertilizer dispenser with a water inlet and outlet. Examples of this group include the Gardena fertilizer injector and the Chapin fertilizer injectors (Amazon Link).

Gardena Fertilizer dispenser

To use, simply connect the fertilizer dispenser to the irrigation pipeline. If the system is designed for micro-irrigation with a low maximum pressure, a pressure reducer must be installed upstream. Pour the fertilizer into the reservoir and activate the fertilizer mixing mechanism using the lever. Water flows into the reservoir at the bottom, mixes with the fertilizer, and is then flushed out as a water-fertilizer mixture through the outlet at the top of the reservoir and distributed via the irrigation system.

A dosage ratio cannot be set. Instead, the amount of fertilizer to be added is calculated based on the water requirements of the planned irrigation cycle and the liquid fertilizer manufacturer’s dosage recommendation, and then poured into the reservoir. For example: If an irrigation cycle with a water consumption of 10 gallons is planned, and the liquid fertilizer manufacturer’s dosage recommendation is 0.004 gallons or 0.5 fl oz per gallon of water, then 0.04 gallons or 5 fl oz  of fertilizer should be added to the fertilizer reservoir. If water consumption is unknown, it can either be measured or, in the case of a micro-irrigation system, estimated based on the number of drippers used (e.g., if the system uses 40 0.5 gallon drippers, then the water consumption is 20 gallons per hour).

Some systems include a filter that, in addition to liquid fertilizer, also allows the use of filter granules that dissolve in the water flowing through them. The filter prevents undissolved granules from entering the irrigation system.

The fertilizer dosage in such systems is not constant; it is highest at the beginning of the irrigation cycle and then gradually decreases. As the irrigation cycle progresses, the fertilizer-water mixture will contain very little fertilizer.

A crucial factor when choosing a system is the capacity of the reservoir. The reservoir of the Gardena fertilizer dispenser, for example, holds a maximum of only 10 fl oz. This means that refilling is absolutely necessary before each watering cycle. However, the small size might also be insufficient for a single watering session, requiring multiple refills within that cycle. Chapin also offers models with larger reservoirs, which are also suitable for slightly higher pressure (up to 40 psi compared to 22 psi for Gardena).

Gardena Fertilizer Dispenser in a Quick Test

For this article, I put the Gardena fertilizer dispenser through a short test. First, let’s look at what’s included: For around $20, you get the device itself along with two adapters that allow you to convert the inlet and outlet from the larger 1/2 inch supply pipe to the smaller 1/4 inch distribution pipe, so you can also connect the smaller distribution pipe as an alternative. A brief instruction manual is also included, but the operation is essentially self-explanatory.

The fertilizer dipsenser appears to be of high-quality construction, with a heavy, well-fitting plastic lid. It has a maximum capacity of 0.08 gallons. A practical feature: When filling, you can see how much fertilizer has already been added thanks to the markings on the side, making it easy to approach a specific target amount.

A look inside with the practical fill level markings

I simply placed the fertilizer dispenser in front of a micro-irrigation zone. Specifically, after the pressure regulator, as the pressure inside the device must not exceed 22 psi.

This is how to connect the device (pressure regulator on the left).

The installation direction is indicated by an arrow on the device. Before starting, the lever must be set to “Mix” and then irrigation can begin. The other setting, “Service,” is for draining the water from the bottom of the reservoir to empty it. In my test, the operation worked flawlessly, but the micro-irrigation area I watered would probably be too large for real-world use, as evidenced by the fact that the fertilizer solution was washed out of the device in no time. In practice, I would doubt that the fertilizer would then be distributed evenly to the plants.

Conclusion: The Gardena fertilizer injector works reasonably well, but in my opinion, it is really only suitable for very small micro-irrigation applications, such as on a balcony or a small patio. As soon as the area becomes larger, I would recommend a system with a larger reservoir.

Alternatives to the Gardena Fertilizer Mixer

Besides Gardena, I am only aware of the Chapin Hydrofeed devices with the same principle. There is the Hydrofeed 4700 to 4702 (Amazon Link), a device that is built on the same principle as the Gardena fertilizer mixer, but is designed for hanging rather than standing installation. It is offered with fertilizer capacities of 16, 24, or 32 ounces. And then, from the same company, there is the much larger Hydrofeed 4720 with a comparatively large 2 gallon tank and an injector section separate from the tank.

Venturi Injector

This method of fertilization, known for centuries, utilizes a physical principle: When a liquid is forced through a constriction, its velocity increases at that point, while the outward pressure exerted by the liquid decreases. This can be explained by the formula: Total pressure = Flow pressure + Static pressure. Therefore, if the flow velocity (= flow pressure) increases, the outward pressure (= static pressure) must decrease. If the constriction through which the water is forced through a pipe is narrow enough, there is no pressure at all on the outer walls; instead, a vacuum is created. This means that if there were a hole in the outer wall at this constriction, no water would escape; instead, if you placed your finger on it, you would feel a suction.

The so-called Venturi nozzle utilizes this principle. A smooth-walled pipe is significantly narrowed in the middle, and a suction hose leads from this constriction, utilizing the vacuum to draw in a liquid or gas.

Example of a Venturi injector in use

Alternatively, the Venturi nozzle can also be installed in a bypass branch that diverts from the main line. Such a bypass has the advantage that only a portion of the water flow passes through the Venturi nozzle (allowing for larger volumes of water) and that a valve installed in the main line can be used to slow down the water flow, creating a controlled pressure differential and thus controlling the intensity of the fertilizer application.

In agriculture, such Venturi nozzles have been used for fertilization for many decades. Their advantage: They utilize existing water pressure to deliver the liquid fertilizer, and they are very easy to install and compatible with fertilizer tanks of virtually any size. Disadvantages: The Venturi principle requires pressure, and the fertilizer intake results in a loss of water pressure. Furthermore, the fertilizer dosage is pressure-dependent and therefore not constant under fluctuating pressure.

More information on how the Venturi injector works, including a short test report, can be found in a separate article: Fertilizing with a Venturi Injector

Differential Pressure Fertilizer Tanks

These systems function similarly to the previously described fertilizer injectors, but are significantly larger and additionally utilize a bypass (diversion) to create a controlled pressure differential. This allows for precise control over the force with which the water-fertilizer mixture is drawn from the tank. Part of the water flow continues directly through the main line, while another part takes the detour via the new bypass into the fertilizer tank. There, the water mixes with the fertilizer, and the resulting mixture is then transported and distributed.

A valve is installed in the main line at the bypass point to slow down the water flow. The greater the slowdown, the greater the pressure differential between the tank inlet and outlet, and consequently, the stronger the water-fertilizer mixture is drawn from the tank.

As with fertilizer injectors, the dosage in differential pressure tanks is not constant: The fertilizer concentration in the dispensed water is high at the beginning, decreases continuously with the water flowing into the tank, and is very low at the end of the irrigation. Therefore, as with fertilizer injectors, there is a risk of overdosing fertilizer in some areas and underdosing it in others.

Compared to a Venturi injector, the application is somewhat simpler. However, significantly less controlled fertilization is possible. The generation of differential pressure also results in a pressure drop in the fertilizer tank.

Dosing Pumps

These are mechanical pumps, meaning they operate without an electrical connection. They are also known as “Positive Displacement Injectors.” The principle is similar to that of another type of piston pump, the traditional hand pump. Water from a pump or the mains water supply flows into the pump and drives the piston. The piston’s stroke adds fertilizer to the water, and the water-fertilizer mixture is then pumped on the other side of the pump. The dosing ratio can be adjusted on the pump.

Dosing pumps are a very professional method of fertilization and have the significant advantage that the dosing ratio remains constant regardless of the water pressure and flow rate, as the same amount of water and fertilizer is mixed with each up-and-down movement of the piston. However, they are considerably more expensive than Venturi nozzles. As with Venturi nozzles, dosing pumps also experience a certain water pressure loss, which depends on the water flow rate. For example, the Tefen Mixrite TF-125-04 has a pressure loss of 3 psi at a flow rate of only 50 gallons per hour and 17 psi when operating at the maximum flow rate of 660 gallons per hour.

Dosing pumps from brand-name manufacturers like Dosatron or Tefen start at around $500, but generic models are also available on Amazon and eBay starting at approximately $150 (Amazon Link).

Electric Dosing Pumps

These are the top-of-the-line fertilization systems. They function on the same basic principle as the previously described dosing pumps, by dispensing water and fertilizer in a predetermined ratio and then pumping it onward. The only difference is that the drive is electric, for example, with a pump controlled by the water flow. They are significantly more expensive than their manual counterparts and therefore generally unaffordable for private users.

Conclusion and Recommendation

Differential pressure fertilizer tanks are only used in a few regions of the world and are rarely available on the market. Due to their high price, electric dosing pumps are not a viable alternative for private users. This leaves you with four basic alternatives:

• Manual watering using special fertilizer sprayers, fertilizer containers with spray attachments, or pump sprayers
• Fertilizer mixing dispenser
• Venturi nozzle
• Mechanical dosing pump

If you don’t want to invest much, have minimal setup effort, and don’t mind a little manual work when fertilizing, then the options mentioned at the beginning of this report for integrating liquid fertilizer into a manual system are worth considering.

For small and medium-sized micro-irrigation systems, fertilizer mixing dispenser offer a very simple and effective alternative. The container is simply placed in front of the micro-irrigation area, and the fertilizer is gradually flushed out during watering. For small-scale applications, where only a few plants on a balcony or patio are being micro-irrigated and the water flow is low, the Gardena fertilizer dispenser is suitable. For medium-sized systems, Chapin fertilizer injectors are recommended, and for larger micro-irrigation systems, the large 2 gallon Chapin Hydrofeed 4720 tank is ideal.

A more professional fertilization method, allowing for active regulation of fertilizer dosage and ensuring consistent application, is possible with Venturi injectors. These have been used in agriculture for many decades and can be easily integrated into an existing irrigation system using a bypass. The tank size is flexible, as any suitable container can be used. A more powerful pump is required, as the Venturi nozzle noticeably reduces water pressure.

For home users, the ultimate solution is the mechanical dosing pump. This system is significantly easier to use than the Venturi injector and guarantees consistent dosing even under fluctuating pressure. The fertilizer dosage can be easily adjusted via a lever. However, especially with brand-name equipment, it is many times more expensive than the Venturi injector.

Der Beitrag This way, garden irrigation can be used for fertilization. erschien zuerst auf Irrigation Blog for Do-it-yourselfer.

Among the sprinklers available on the market, the Rain Bird Maxi Paw has a unique selling point: it’s the only pop-up impact sprinkler I know of. Impact sprinklers have largely disappeared from private gardens in recent decades with the rise of gear-driven sprinklers. However, they can still be a viable alternative in challenging water conditions. In this article, I’ve taken a closer look at the Rain Bird Maxi Paw.

What are impact sprinklers?

Impact sprinklers are the sprinklers many people remember from their childhood. Impressive devices with a powerful spray, usually mounted on a tripod, they made quite a bit of noise when operating and sprayed a lot of water in the immediate vicinity. This last point made them particularly popular with children, as they could stand next to them in the summer and enjoy a pleasant cooling spray.

This water distribution is achieved by the jet separator, a usually rod-shaped barrier mounted in front of the nozzle. The water shooting through the nozzle hits the jet separator and deflects it to the side. A spring then returns the jet separator to its original position, where it is struck by the jet again. Each deflection causes the sprinkler to rotate a small amount. The impact of the jet on the jet separator creates the characteristic tapping sound of this type of sprinkler and distributes the water in the immediate vicinity.

When is an impact sprinkler necessary?

Impulse sprinklers are still commonplace in agriculture. However, they have become rare in private gardens. Gear-driven sprinklers, sprayers, and rotators have gradually replaced impact sprinklers. These offer several advantages over impact sprinklers: They are significantly quieter, provide more even watering, and are easier to adjust.

The first point is particularly important, as private gardens are usually built right up against the neighbor’s fence, and the impact noise of a sprinkler can be quite loud and perceived as disruptive. Modern gear-driven sprinklers aren’t completely silent either, but they produce a quieter and much more consistent sound.

Therefore, aside from nostalgia, there’s currently no real reason to opt for an impact sprinkler. With one exception: If you only have slightly dirty water available for irrigation, containing sand or sediment, then an impact sprinkler can be a welcome solution!

Gear-driven sprinklers struggle with such conditions, as their gears can become clogged and quickly stop functioning correctly. This is usually solved by using a filter to ensure the water is clean before entering the pipeline. However, with very fine sand, algae, or organic contaminants, this can be difficult and expensive, and may also require a relatively high water pressure.

This explains why the Rain Bird Maxi Paw continues to hold its own in the Rain Bird product range: as a virtually indestructible, robust workhorse, its exposed mechanics and straightforward, simple design make it relatively insensitive to harsh conditions, and it performs reliably even in challenging environments. And I only recommend using it for this specific application; otherwise, a modern gear-driven or rotary sprinkler is a better choice!

Rain Bird Maxi Paw Under the Microscope

What immediately stands out about this sprinkler is its comparatively enormous size. This applies not only to the cap, which has a much larger diameter than other sprinklers, but also to the sprinkler itself.

The relatively large height might make connecting it to the pipeline a bit more difficult. However, the Maxi Paw addresses this by providing not only the standard 3/4-inch connection at the bottom, but also an optional 1/2-inch connection on the side. To use the latter, simply unscrew the plug from the side connection, thus sealing the bottom connection. Even if it doesn’t look like it at first glance: The plug is large enough for this, as the 3/4 inch connection at the base of the sprinkler tapers inwards.

Size comparison of Rain Bird Maxi Paw with Rain Bird 3500 gear-driven sprinkler

Variants

The full name of the sprinkler is Rain Bird Maxi Paw 2045. The 20 indicates the minimum throw distance of 20 feet (6 meters), and the 45 indicates the maximum throw distance of 45 feet (13.7 meters). One or more letters follow to distinguish the four variants:

• 2045A – The standard model
• 2045A-NP – Same as above, but with a purple cap instead of black, indicating the use of grey water
• 2045A-SAM – With an additional Seal-A-Matic check valve, which prevents puddles from forming when used on uneven terrain
• 2045A-SAM-NP – With a purple grey water cap and Seal-A-Matic check valve

The “Maxi” in Maxi Paw is there because there was previously a smaller model called the Mini Paw. This model has since been discontinued.

The sprinkler is available with a total of 7 different nozzles. The five nozzles 06, 07, 08, 10, and 12 allow for smaller or larger water flow rates and throw distances, respectively. The two nozzles 07LA and 10LA are low-angle nozzles that distribute the water at a shallower angle than the other nozzles. This can be advantageous in areas with strong winds.

Key data Rain Bird Maxi Paw

Name

Rain Bird Maxi Paw

Maximum possible radius:

65 ft. (13.7 m)

Minimum possible radius

30 ft. (6 m)

Adjustable arc

40° to 360°

Water pressure range

25 to 60 psi (1.7 to 4.1 bar)

Water consumption

1.5 to 8.4 gpm (5.6 to 31.8 L)

Precipitation rate

0.28 to 1.21 in/hr (7 to 31 mm/h)

MPR nozzles

Pressure regulation

Inlet size

3/4 inch male thread or alternatively 1/2 inch female thread

Price

$37.99

Name

Rain Bird Maxi Paw

Maximum possible radius:

65 ft. (13.7 m)

Minimum possible radius

30 ft. (6 m)

Adjustable arc

40° to 360°

Water pressure range

25 to 60 psi (1.7 to 4.1 bar)

Water consumption

1.5 to 8.4 gpm (5.6 to 31.8 L)

Precipitation rate

0.28 to 1.21 in/hr (7 to 31 mm/h)

MPR nozzles

Pressure regulation

Inlet size

3/4 inch male thread or alternatively 1/2 inch female thread

Price

$37.99

Adjustment

Adjusting the sprinkler isn’t rocket science. However, compared to modern sprinklers that make it very easy, it’s still a bit more challenging. You can adjust the irrigation sector (either a full circle or a setting from 20 to 340 degrees) and the throw distance using the adjustment screw (according to the manufacturer, a reduction of up to 25% is possible). The nozzles can also be changed.

A special adjustment tool is sold for the Maxi Paw sprinkler, which helps you pull out the riser and lock it in place. This is convenient and certainly not a bad idea if you have many sprinklers to adjust, but the adjustment can also be done by hand or with simple tools.

To pull out the riser, you need a very narrow tool, such as a very flat screwdriver or a flat spatula, to reach into the gap between the riser and the body and pry and pull it out. Instead of using the special adjustment tool to secure it, you can simply hold it in place with your own muscle power and make the necessary adjustments.

Moving the adjustment loops to set the irrigation sector and turning the deflector screw to reduce the spray distance requires no tools; this is done by hand. Changing nozzles is also easy: simply twist them 90 degrees, pull them out, and reinsert them in the same way.

Alternatively, the settings can be adjusted during actual operation, once the sprinkler is supplied with water and extends automatically. This saves you from having to hold the riser, but you shouldn’t mind getting wet, as it’s quite easy to do so.

Personal Impression

What immediately stands out, especially if you’re used to gear-driven or rotary sprinklers, is the forceful spray pattern. It feels significantly less elegant and refined than what you’re used to, but in my opinion, this isn’t a drawback for the intended application, as it explains why the Maxi Paw is much less affected by dirty water. The water is channeled through so directly and efficiently that no dirt can remain in the sprinkler.

In my test, the sprinkler function worked flawlessly. I also found the settings straightforward, and you don’t really need the additional adjustment tool. Simply use the metal adjustment loops to define the area to be irrigated, and you’re good to go. You only need to adjust the limit screw if you need to reduce the spray distance. I also tried changing the nozzle, which is equally simple. Just turn the nozzle 90 degrees and remove it. Then place the new one on top and turn it back 90 degrees to lock it in place.

With the available nozzle set, a matched precipitation rate across multiple sprinklers (MPR) is also possible. A pressure-regulating body is not offered for the Maxi Paw.

The noise level is significantly higher than with gear-driven or rotary sprinklers; it sounds a bit like the rattle of a machine gun. If you or your neighbors are sensitive to noise, an impact sprinkler is not ideal. To give you an idea, I’ve included a short video below showing the sprinkler operating for a few seconds and the noise it produces.

Video of the Bird Maxi Paw in action

In my experience, the Maxi Paw sprinkler irrigates more intensively in its immediate vicinity than gear-driven and rotary sprinklers, which only irrigate very weakly in this area. This would be a factor if the Maxi Paw were used as a standalone unit. In practice, however, impact sprinklers, like gear-driven and rotary sprinklers, should also be used in conjunction with other sprinklers in a square pattern or triangular pattern. This ensures that any uneven watering of one sprinkler is compensated for by the neighboring sprinklers.

In conclusion: If you have a choice, you don’t need to opt for the Maxi Paw, as there are now more modern and better sprinklers on the market, and it does have certain drawbacks. However, for heavy-duty work in difficult water conditions where other sprinklers fail, it is a well-functioning alternative! The sprinkler reliably does what it’s supposed to and, while not quite as easy to use as some other sprinklers, is still quite simple to operate. One drawback is the relatively large area it occupies in the lawn and the somewhat higher operating noise.

Where to buy

The sprinkler is available for around 20 dollar in garden centers, specialist shops and on Amazon (link to product).

Der Beitrag Rain Bird Maxi Paw as a sprinkler alternative in difficult water conditions erschien zuerst auf Irrigation Blog for Do-it-yourselfer.

Der Beitrag What different types of sprinklers exist? erschien zuerst auf Irrigation Blog for Do-it-yourselfer.

Even if you’ve planned everything perfectly, redesigning your garden may require adapting an existing irrigation sector and relocating sprinklers to other locations or deactivating them. The best way to proceed depends primarily on whether the change is permanent or temporary. There are basically two options:

• Remove the sprinkler completely from the pipeline
• Leave the sprinkler in the pipeline, but ensure it no longer releases water

If the deactivation has a limited expiration date and the sprinkler is to be used as usual afterward, the second option is recommended, for example, if you set up a sandbox for your children in the garden for a few years, but already know that it will disappear again afterward. Or, for example, if a renovation involves temporarily dedicating a section of the garden to storage and not watering it. However, if the renovation is permanent and renders the sprinkler obsolete, it should be removed completely.

Turning off sprinklers

On the one hand, there are sprinklers and sprayers that have a shut-off function. This includes all Hunter and Rain Bird spray nozzles, whose water flow can be reduced to zero using the adjustment screw. This is also possible with the Gardena SD30 and SD80 pop-up sprayers. Hunter and Rain Bird also offer this option for their state-of-the-art Hunter I-20 and Rain Bird 5000 plus gear-driven sprinklers. Shutting off ensures that no water is released, but the sprinklers still rise. All older Hunter and Rain Bird gear-driven sprinklers and all other Gardena sprinklers do not have an integrated shut-off option.

With the Hunter MP Rotator, there are two options: For Pro-Spray, PRS30, and PRS40 bodies, there are special Hunter sealing caps that can be screwed on instead of the standard cap to seal the bodies at the top. Alternatively, you can screw a Hunter blind nozzle onto all bodies with a 5/8-inch external thread riser instead of standard nozzles. In this case, the nozzle still rises, unlike the previous version, but no longer releases water. These practical shut-off caps and blind nozzles are rarely available in stores. Without knowing exactly what you’re looking for, it’s difficult to find these products, so here are two direct Amazon links*:

• Amazon offer: Hunter Pro-Spray Cap
• Amazon offer: Hunter Blind Nozzle

Removing the sprinkler and closing the connector

If the sprinkler doesn’t offer any of the options listed above, or if you want to remove it permanently anyway, the easiest way is to remove it and seal the connector attached to the pipeline with a cap. To do this, proceed as follows:

The theoretically possible minimum is to unscrew the sprinkler from the top of the connector by twisting it and then pull it out of the ground. The connector thread is then exposed, and if you have very narrow hands and a lot of fingertip strength, you could theoretically unscrew the cap right away.

In practice, however, this doesn’t really work. On the one hand, there’s a very high risk of accidentally getting soil into the pipeline, and on the other hand, the narrow access makes it almost impossible to exert enough force to properly unscrew the cap, and you also don’t have the necessary space to wrap the thread with Teflon tape beforehand to seal it!

Therefore, you’ll have to invest a few extra minutes and dig a few centimeters around the sprinkler. This is done before unscrewing the sprinkler from the thread to prevent soil from falling into the pipeline during excavation work. Only after the connection point has been thoroughly exposed and cleaned should the sprinkler be unscrewed. If it was mounted on a swing joint, both the sprinkler and the swing joint are removed. Now carefully wrap Teflon tape around the thread of the connector and screw on the cap. It is sufficient to tighten it by hand; no tools are required. Then, pressurize the irrigation system and check that the cap is tight. If everything is correct, the hole can be filled again.

Step-by-step process in pictures:

Special case: When the sprinkler is the last one in the line

The procedure described should be omitted if the sprinkler to be removed is the last one in the line and the pipeline is blown out with compressed air before winter. In this case, this would create a dead end in the irrigation system, where the water would stagnate during the winter and could cause frost damage. Therefore, in such a case, the plug is installed at the sprinkler that was previously passed through in the line. This means the next one in the direction of the water source from the sprinkler to be removed. Immediately after this sprinkler, the pipeline pipe is cut off and an end cap or connector end piece is installed. The removed sprinkler then no longer needs to be plugged, as the upstream section of pipe no longer serves any function. Here, too, a leak test must be performed before filling the pipe.

Caps/Blank Plugs

Caps and blank plugs are available in plastic or metal and are available from irrigation companies such as Rain Bird or Gardena and a variety of other companies. Most sprinklers require caps with a 1/2-inch internal thread; larger sprinklers also require caps with a 3/4-inch internal thread. Some caps include an internal sealing ring, eliminating the need for additional sealing with Teflon tape.

Der Beitrag How do you deactivate a sprinkler that is no longer needed? erschien zuerst auf Irrigation Blog for Do-it-yourselfer.

Principle of the Venturi Nozzle

A Venturi injector is based on the Venturi nozzle invented by Giovanni Battista Venturi over 200 years ago: This is a smooth-walled tube with a sharp constriction in the center, from which an opening leads downwards. At the constricted point in the tube, due to the laws of physics, the velocity of the water flowing through it increases (= increasing flow pressure), while at the same time the static pressure on the tube wall decreases; total pressure = flow pressure + static pressure. The constriction in a Venturi nozzle is designed so large that the static pressure at the constriction not only decreases, but even creates a negative pressure (vacuum). This means that no water escapes from the opening leading away from the constriction; on the contrary, a suction is created.

How a Venturi Injector Works

The suction created by the flow through the Venturi nozzle is used to draw in a gas or liquid via a hose mounted at the constriction. In the application described here, liquid fertilizer is drawn in. For this purpose, the hose is simply led away from the Venturi nozzle into a container containing fertilizer. As soon as irrigation is running, the created suction ensures that the fertilizer is gradually mixed into the irrigation water.

At the opening from which the fertilizer intake hose leads, a mechanism is installed in the Venturi nozzle that prevents water from flowing into the fertilizer container. In practice, this would occur when irrigation is stopped, thus creating pressure at the intake opening instead of a negative pressure. The water remaining in the irrigation system would then be forced outward and flow into the fertilizer container.

In most Venturi injectors, the backflow prevention mechanism works with a small spring that pushes a plastic ball in front of the outlet, thus closing it. Only when sufficient suction is applied does the ball retract, opening the outlet so that the fertilizer can be drawn in.

Intake outlet ready for use and below with removed seal, ball and spring

The ratio of fertilizer addition is primarily determined by the following three parameters:

• Diameter of the Venturi nozzle and the nozzle constriction
• Inlet pressure at the inlet of the Venturi nozzle
• Outlet pressure at the outlet of the Venturi nozzle

The following applies: The greater the pressure difference between the inlet pressure (at the inlet of the nozzle) and the outlet pressure (at the outlet of the nozzle, after passing the constriction), the greater the suction effect and, consequently, the more fertilizer is added. This difference is achieved, on the one hand, by the constriction in the Venturi nozzle, as the water loses pressure due to the strong friction when passing through the constriction. The narrower the constriction, the greater the pressure loss. When installing the Venturi nozzle via a pipe bypass, the pressure difference can be further increased by deliberately slowing the water flow upstream of the outlet side of the Venturi nozzle with a valve, allowing the fertilizer dosage to be controlled according to your preferences.

Depending on the model, Venturi injectors require at least a 20 to 30% pressure difference between the inlet and outlet of the nozzle to function. A difference of around 50% typically achieves the maximum possible fertilizer dosage. The minimum pressure difference required to draw in fertilizer cannot be achieved with all Venturi injectors and at all inlet pressures using only the Venturi nozzle; in some cases, creating an additional pressure difference using a bypass is absolutely necessary.

The maximum technically achievable mixing rate for a Venturi injector is a maximum of 10% (i.e., 1 gallon of fertilizer to 10 gallons of water). For the sake of completeness: In addition to the size and design of the Venturi nozzle, the inlet and outlet pressures, other factors can have a minor impact on the dosage ratio: the liquid fertilizer used (viscous or watery), how deep the fertilizer container is placed below the nozzle, the outside temperature, and the elevation of the application site.

The diameter of the Venturi nozzle, the inlet pressure, and the outlet pressure also determine how many gallons of water per hour can flow through the nozzle in this configuration. Quality manufacturers list these parameters for each nozzle size and different inlet and outlet pressures in performance tables. Below is the example performance table for Irritec’s Venturi injectors:

Performance table of Irritec Venturi injectors

The first column shows the inlet pressure, followed by a range of possible outlet pressures. For each combination of inlet and outlet pressure, the corresponding water flow and fertilizer output are listed. This is for four different Venturi injector models ranging in size from 3/4 inch to 2 inches.

An example explains how to read such a table:

Using a 3/4-inch injector, an inlet pressure of 4.10 bar (60 psi), and an outlet pressure of 3.0 bar (43 psi), a flow of 36 liters per minute (10 gallons per minute) or 2,160 liters per hour (570 gallons per hour) is possible, and the fertilizer addition would be 66 liters (17 gallons) per hour. With a 1-inch injector, the water flow at the same pressure would be 4,560 liters per hour (1.200 gallons), and the fertilizer addition would be 230 liters (60 gallons).

What determines the outlet pressure?

The outlet pressure is determined by the requirements you want to meet with the fertilizer water. If the water were simply allowed to flow freely out of the pipe immediately after leaving the Venturi nozzle, a pressure close to zero on the outlet side would be sufficient. In this case, a valve installed in the bypass could reduce this pressure to near zero, thus exploiting the maximum possible pressure difference and achieving the highest possible fertilizer dosage.

However, if the fertilizer water still has to exert considerable pressure after leaving the Venturi nozzle – as is usually necessary in an irrigation system – to travel the distance through the irrigation pipeline and then ensure the sprinklers extend and function correctly, a significantly higher pressure is required on the outlet side.

This is essentially the same consideration as when calculating the water flow rate in an irrigation system. For example, if the sprinklers require 40 psi and there is a further pressure loss of 10 psi in the pipeline due to friction, then 50 psi of pressure would be needed on the outlet side just to exert the necessary static pressure in the irrigation system. At such a pressure, however, the entire output pressure would be used for static pressure, leaving no dynamic pressure to drive the water through the pipes. For irrigation to function with a reasonable amount of water, a slightly higher output pressure than 50 psi would be required. According to a practical example used here in the blog, for example, with the water source used there, you would need 60 psi to achieve a water output of 280 gallons per hour with a pressure requirement of 50 psi in the irrigation system.

This shows that in practice, you have to weigh and balance between higher fertilizer dosage and still sufficient output pressure, and in many cases, you will have to focus on the lowest possible dosage. Unless you use the Venturi injector for micro-irrigation, which has significantly lower pressure requirements, or you have a very powerful pump available that still has considerable reserves for everyday irrigation needs.

Advantages and Disadvantages of Fertilization with a Venturi Injector

The main advantage of fertilization with a Venturi injector is that it is very easy and cost-effective to implement. Furthermore, Venturi injectors are simple and have no moving parts, so almost nothing can break during operation and they are therefore very low-maintenance.

A significant disadvantage is that the Venturi nozzle relies on the existing water pressure to function. Bernoulli’s law “Total pressure = flow pressure + static pressure” only applies one-to-one to frictionless fluids, which water is not. Therefore, when water flows through the constriction of the Venturi nozzle, friction losses occur and, consequently, pressure losses. The function of the Venturi nozzle is based precisely on this pressure loss, which leads to the pressure difference.

Depending on the nozzle model, a pressure drop of at least 20 to 25% is required for proper functioning. If the natural pressure loss through the nozzle is insufficient, the water must be additionally slowed down in a bypass system with a valve.

Consequently, the use of a Venturi injector leads to a certain pressure loss, so that the pressure ratios previously present in an irrigation system are no longer 1:1, and irrigation may then no longer function as perfectly as before (reduced uniformity). It is comparatively easy to use in micro-irrigation systems, which operate at low pressure. Therefore, reducing the pressure hardly plays a role in such systems.

For use in conventional irrigation, e.g., for watering the lawn, a powerful pump is advantageous, so that sufficient pressure remains for irrigation after the water has passed through the Venturi nozzle, and irrigation continues to function properly.

Compared to fertilizer systems with a dosing pump, a Venturi injector also has the disadvantage that the amount of fertilizer delivered depends on the pressure conditions. This makes it difficult to precisely adjust and maintain the fertilizer dosage, especially if the irrigation system is subject to fluctuating pressure conditions.

Finally, correctly adjusting the Venturi injector for the first time requires some effort, especially if you want to set the dosage to a predetermined level. After setup, the installation is ideally left untouched so that the desired adjustment can be used permanently.

How to Install the Venturi Injector

The Venturi Injector is typically installed in the main pipeline, i.e., in the section of the pipe at the beginning of the system that is passed through during each irrigation run, before the main line then splits into several branches for the individual irrigation sectors.

To prevent the risk of backflow of water mixed with fertilizer toward the water source, a backflow valve should be installed between the water source and the fertilization system, or the Venturi nozzle should be isolated from the main system with manual valves after fertilization. If drinking water is used directly from the drinking water system, the stricter regulations regarding drinking water protection must be observed.

The Venturi Injector can either be installed in-line with the main pipeline or in a branch (bypass) that diverts from the main pipeline to the Venturi Injector and returns to the main pipeline after the fertilizer has been absorbed.

Such a bypass installation has the following advantages:

• With a valve installed in the main line at the level of the bypass between the bypass inlet and bypass outlet, you can control the pressure difference between the inlet pressure and the outlet pressure of the Venturi nozzle, thus adjusting the fertilizer dosage. Some manufacturers even specify this type of installation to ensure their injector functions properly, or even strongly recommend it, because the Venturi nozzle alone cannot create the necessary pressure difference, or not in every pressure configuration.
• Furthermore, a bypass solution has a positive effect on water flow, as some of the water can bypass the Venturi nozzle and take the direct route through the pipeline. This enables higher flow rates than the Venturi nozzle itself would allow.
• The bypass can be deactivated relatively easily with valves installed in between, so that during normal non-fertilizer irrigation runs, the water does not have to flow through the Venturi nozzle. If the injector were installed directly into the main line, it would have to be removed every time after use to achieve the same result. The bypass, on the other hand, only needs to be installed once and can then remain as it is permanently.

Below are four possible installation methods for a Venturi injector from the Irritec user manual. In addition to the connection directly into the pipeline and the standard bypass connection, two alternative connections with an additional pump are also listed:

Four possible installation types

The Venturi injector should always be mounted horizontally or, alternatively, vertically upward (i.e., inlet at the bottom and outlet at the top). A vertically downward position can cause suction problems. The water must flow through the nozzle in the specified direction; this direction is indicated on the nozzle.

By installing a pressure gauge on the inlet and outlet sides of the bypass, the inlet and outlet pressure can always be precisely monitored, or a specific pressure difference can be set using a valve.

Since airtight connections are important for proper operation, it is recommended to use PE tape or other sealing material on the threads during installation. Ideally, the complete injector, i.e., both the nozzle and the suction hose, should be purchased from the same manufacturer to ensure optimal compatibility.

The suction hose is suspended completely down to the bottom of the fertilizer tank so that the fertilizer can be drawn all the way to the bottom. At the end of the suction hose there is usually a small filter basket that prevents the suction of larger protective particles.

How to Choose a Suitable Venturi Injector

The most important selection criterion is the size of the injector! This is not determined by the size of the pipeline used in the irrigation system, but by the available pressure and water flow rate. Specifically, the water flow rate achieved during operation, not the maximum available! This is further exacerbated by the fact that the Venturi nozzle requires a significant pressure reduction of 20% or more to function, and the water flow rate when using a Venturi nozzle will therefore be somewhat lower than in previous irrigation runs without a Venturi nozzle. Unless you haven’t yet fully utilized the potential pump capacity or the power from the domestic water supply, so you still have some reserves.

If in doubt, or if you’re unsure about the water flow rate, it’s better to buy a smaller Venturi injector!

If the injector is too large and the specified flow rate is not reached, the injector will not draw in any fertilizer. If the injector is too small, however, fertilization will work perfectly, but the injector will limit the flow. This problem can be solved relatively easily by incorporating it into a bypass so that excess water can bypass the nozzle.

Note: Micro-irrigation sectors are particularly problematic for Venturi injectors if they have very low water flow rates. Here, you must carefully find a suitable injector or, if that is not possible, use a different fertilization system altogether.

Regarding water flow, it is important to note that even with the same diameter, Venturi injectors can have very different performance characteristics. There are 3/4-inch injectors designed for high water flow and others for low water flow. The manufacturer Mazzei, for example, offers both the IM34L model with a minimum flow rate of 240 gallons/hour at 50 psi inlet pressure and the IM34H model with a minimum flow rate of 420 gallons/hour at 50 psi inlet pressure in 3/4-inch sizes. They also offer a 1/2-inch injector with a low flow rate of 60 gallons/hour or a high flow rate of 150 gallons/hour (IM12L and IM12H). The 3/4-inch Irritec model I tested requires approximately 500 gallons/hour at an inlet pressure of 50 psi.

The possible fertilizer dosage is only a secondary selection criterion. Liquid fertilizer manufacturers specify a specific dosage ratio for their products, which the injector should be able to achieve. However, it is particularly important not to apply the fertilizer too concentrated, as this could damage the plants. However, this problem will rarely occur with Venturi injectors, as higher dosages require more pressure. When fertilizing with an irrigation system, it is generally recommended to apply the fertilizer slowly, as this allows for greater uniformity.

Products Available on the Market

Complete Venturi injectors, consisting of a nozzle and intake hose, as well as nozzles and intake hoses separately, are available on the market. Venturi injectors are available either as a standalone product, i.e., just the nozzle and a matching intake hose, or as part of a pre-assembled bypass. This saves you the trouble of assembling such a bypass yourself.

Numerous no-name products are available, as well as products from brand manufacturers such as Netafim, Irritec, or Mazzei. No-name Venturi injectors start at $20 to $30, while brand-name products cost approximately $60 to $100. A Venturi injector in a pre-assembled bypass solution will cost approximately $30 to $200 more, depending on the quality of the bypass and whether it includes a built-in pressure gauge. Some injectors also offer a way to adjust the dosage by using a valve on the intake hose to slow the suction.

Venturi injectors on Amazon:

Unlorspy 2Pcs Black Venturi Injector Tube 1/2 Inch Agriculture Garden Fertilizer Injector Plastic Irrigation Venturi Injector for Irrigation Systems (1/2 Inch)

$9.69 (as of 17. March 2026 16:04 GMT +01:00 - More infoProduct prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on [relevant Amazon Site(s), as applicable] at the time of purchase will apply to the purchase of this product.)

AYLIFU 3/4Inch Black Irrigation Venturi Fertilizer Injector Tube Venturi Fertilizer Mixer Injector for Outdoor Garden Agricultural Irrigation Equipment Tools

$8.99 (as of 17. March 2026 16:04 GMT +01:00 - More infoProduct prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on [relevant Amazon Site(s), as applicable] at the time of purchase will apply to the purchase of this product.)

Ozone Venturi Injector for Cold Plunge, Ice Bath, Spa & Pool Pumps, 3/4" Barbed Inlet/Outlet, 1/4" Ozone Port, PVC Water Treatment & Fertilizer Injection for Irrigation

$27.99 (as of 17. March 2026 16:04 GMT +01:00 - More infoProduct prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on [relevant Amazon Site(s), as applicable] at the time of purchase will apply to the purchase of this product.)

UPLYKKE Irrigation Venturi Fertilizer Injector Kit - 1 inch NPT Threaded Interface Venturi Mixer Injector for Automatic Drip Irrigation System Agriculture Garden Water

$19.99 (as of 17. March 2026 16:04 GMT +01:00 - More infoProduct prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on [relevant Amazon Site(s), as applicable] at the time of purchase will apply to the purchase of this product.)

ApplianPar 3/4 Inch Garden Irrigation Device Venturi Fertilizer Kit Mixer Injector Switch Dispenser Water Tube Set

$15.05 $13.20 (as of 17. March 2026 16:04 GMT +01:00 - More infoProduct prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on [relevant Amazon Site(s), as applicable] at the time of purchase will apply to the purchase of this product.)

LQ Industrial 3/4Inch Black Irrigation Venturi Fertilizer Injector Agriculture Irrigation Device Tool

$8.99 (as of 17. March 2026 16:04 GMT +01:00 - More infoProduct prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on [relevant Amazon Site(s), as applicable] at the time of purchase will apply to the purchase of this product.)

Practical Test of the Irritec 3/4-Inch Injector

To give you a concrete example of an application and a starting point for your own further considerations, I tested the Irritec 3/4-inch injector in practice. I tested it with a fairly powerful Grundfos Scala 1 5-55 pump, which still has reserves for its current irrigation task. A pressure of approximately 60 psi is required in the area to be irrigated (40 psi sprinkler, 10 psi pipeline, 10 psi elevation difference when drawing water from the well). The hourly water flow in the tested zone for irrigation without fertilization has so far been approximately 700 gallons.

I screwed the nozzle and intake hose together to form the injector as they came, without any additional sealing material, and installed the injector directly into the pipeline, without a bypass. The intake hose simply hung from there into a standard bucket filled with fertilizer. A very simple design, but perfectly adequate for the test purpose. For permanent use, it could and should certainly be made even more stable and visually appealing.

My simple installation, limited to the essential function, for test purposes

And then an irrigation run was started immediately. Result: The fertilizer intake in the Venturi injector worked perfectly and powerfully, but the sprinklers no longer had the necessary pressure to extend properly and only irrigated at half-mast with significantly reduced throw distances.

Interim conclusion: As expected from the manufacturer’s performance tables (see earlier in the article), the Venturi nozzle limited the maximum possible water flow due to the constriction in the nozzle. This would not be practical in this configuration, as the fertilizer would be distributed very unevenly due to the completely inadequate throw distances.

I then tested the same setup in a second zone, which has a significantly lower water flow of 450 gallons per hour. With this zone, irrigation worked perfectly as usual, with the usual spray distances. And the fertilizer intake also continued to work flawlessly.

Test with installed bypass

I conducted my next test again on the large 700-gallon zone. I quickly built a bypass branch using connectors, pipe sections, and a valve. The bypass branches off downward from the main line, then runs through the Venturi nozzle, and returns to the main line. Parallel to this, the main line continues directly, with an additional valve installed after the branch to the Venturi nozzle to regulate the pressure.

Venturi nozzle integrated into a bypass

In my first test run with the bypass solution, I left the valve fully open so that the water could flow through unhindered. As expected, the irrigation system received sufficient water and functioned as normal. However, the Venturi nozzle did not suck in any fertilizer in this way, as the nozzle constriction was not sufficient in this configuration to generate the required pressure difference.

I then gradually closed the valve until the intake hose began to draw in fertilizer. This was easy to control, and at the lowest possible dosage, where the fertilizer was only sucked out of the bucket very slowly, the irrigation felt almost normal, with only a very slightly reduced throw distance. But even at a higher dosage, it continued to function quite well, with throw distances that were still usable in practice.

Interim conclusion: With a bypass branch, you can easily get closer to the desired result and find a suitable balance between fertilizer dosage and pressure loss.

Test conclusion

The Venturi injector met my expectations: Setup is straightforward and inexpensive, and you can quickly achieve a usable result. Since it allows for significantly more flexible and precise adjustment, I would definitely prefer the bypass installation to the in-line installation for long-term use. The additional installation time only takes a few minutes, or if that’s too tedious for you, you can also purchase ready-made bypass solutions.

Note: After fertilization is complete, you should continue to water with clean water for about half an hour to ensure that all fertilizer residues are washed out of the system and that no algae or microorganisms can form.

Der Beitrag How to fertilize with a Venturi injector erschien zuerst auf Irrigation Blog for Do-it-yourselfer.

In this article, I describe the function of a solenoid valve box in an irrigation system, how to install it, the advantages of using one, and what alternative options exist. I will also introduce some solenoid valve boxes available on the market and show the differences between them.

A solenoid valve box can be used for both regular lawn irrigation and micro-irrigation, and of course, you can also combine both within a single box.

Advantages of Using a Solenoid Valve Box

Using a solenoid valve box offers the following advantages:

Protection from Accidental Damage

This is especially true if you are considering installing the solenoid valves unprotected in the garden as an alternative. Passersby could get caught on such an unprotected structure and inadvertently damage it. Lawnmowers, trimmers, gardening activities, or animals that approach the system out of curiosity or chew on components could also cause damage. The buried box, which is enclosed at the sides and protected by gravel at the bottom and a lid at the top, provides a physical barrier against such damage and also protects against accidental adjustment of settings.

Protection from Wind and Weather

The housing in a solenoid valve box protects the components and wires inside from adverse weather conditions, whether heavy rain, heat, cold, or UV sunlight. It also keeps dirt, debris, moisture, and pests out of the irrigation system. This saves repair costs and extends the life of the system.

Easy Access for Maintenance

A valve box provides easy central access to the solenoid valves, whether in the event of necessary repairs or cleaning, or should a valve need to be replaced. Furthermore, the annual purging of the irrigation system with compressed air can be easily performed centrally via the solenoid valve box.

Neat, visually appealing housing

Unlike exposed valves and cables, a valve box is visually invisible at first glance and unnoticeable. This creates a tidy and clean appearance and does not affect the appearance and aesthetics of the garden.

What does a solenoid valve box consist of?

The following components are used in a solenoid valve box:

• Solenoid valves
• Connecting pipes
• 1 connection fitting for connecting to the supply line
• Several connection fittings at the outlet for connecting to the outgoing pipelines

As well as a few optional components that can be very useful in practice:

• Filter
• Compressed air connection
• Ball valve
• Damp-proof box for wiring

Both solenoid valve boxes and wall-mounted systems are very simple in their basic design: The water flows through a main pipe, from which branches lead either on both sides or on one side at right angles. A solenoid valve is attached to each of these branches, which allows water to flow into the corresponding zone on command or closes again, thus terminating the water supply.

Pipe Connections and Connection Fittings

For residential applications, 1-inch diameter pipes are typically used within the solenoid valve box. The connection fittings on the inlet and outlets of the box are usually either 1-inch or 3/4-inch.

Depending on the size of the pipeline you want to work with, it’s best to go straight for the box with the appropriate fittings to avoid the need for intermediate pieces. The pipe connections are not constructed like standard PE fittings; instead, they use special connectors called valve manifolds.

These are designed to save space, so the box doesn’t have to be unnecessarily large, and the connection points are designed as union joints rather than standard threads. This has the great advantage that the connections in the valve box can be removed relatively easily at a later date without having to disassemble the entire box, allowing, for example, a defective solenoid valve to be easily replaced. It’s also relatively easy to make modifications to the box at a later date.

In this view from below, you can see the cross-piece pipe connections arranged one behind the other to save space.

Such valve manifolds are offered by brands such as Dura, Rain Bird, and Irritec. Unlike the connectors used in pipelines, a cross connector is also offered here, i.e., a connector that distributes the water crosswise in four directions.

Solenoid Valves

In principle, any type of solenoid valve can be used in a valve box. It is only important that the connections match the connections of the pipe connections, as solenoid valves are available in different thread sizes and with both external and internal threads. Some solenoid valves also have a flow regulator built in, such as the Hunter PGV-101, which is not a requirement but can be useful in some situations.

Filters

A sieve or disc filter is often installed at the inlet to prevent contaminants from entering the irrigation system. This filter must be cleaned from time to time. If a filter is already installed in the pump or directly downstream of the pump, then the additional filter in the solenoid valve box is not necessary. A filter basket on the intake opening of a suction hose should not be considered a filter replacement in this regard, as it only filters very coarsely.

Example of a filter

Compressed air connection

This is used to blow out the irrigation system with compressed air before winter. A compressor is connected using a suitable connector, and the water is blown out through the sprinklers or other openings. This is not necessary if the system is designed to drain using a drain valve or a manually opened ball valve located at the lowest point .

Ball valve

This is located in the solenoid valve box on the supply line and allows the water supply to the box to be completely shut off. This can be used for maintenance work in the box or in the event of a leak. It is also practical for closing the connection to the water source when blowing out with compressed air, so that the compressed air can only spread in the desired direction toward the sprinklers.

Waterproof junction box for wiring (cable box)

A waterproof junction box, in which the cable wires of the solenoid valves are brought together, is not mandatory, but it makes connecting the solenoid valves to the water computer easier. This saves you the trouble of creating a waterproof connection yourself, and in many cases, the seller already pre-wired the wiring.

This solenoid valve box includes a waterproof junction box, and the solenoid valves are already connected to the junction box. The wiring to the water computer then runs directly from the junction box.

How do you install a solenoid valve box?

Installation isn’t too complicated and involves the following steps:

Selecting a suitable location for the box

It’s important that the cable connections from the solenoid valves housed in the box to the irrigation computer can be neatly laid, so the solenoid valve box is often placed near the irrigation computer. However, this isn’t mandatory; with 19 AWG cables, distances of up to 300 feet are generally possible.

You’ll only see the lid of the final buried box, so choosing the location can also depend on where in the garden it fits best or is least disruptive. Such lids are quite stable and can be walked on, and some can even be driven over by car (check the manufacturer’s instructions!).

Access to the solenoid valve box isn’t usually needed very often. If you use compressed air, then once a year before the start of winter; if you use a filter in the box, then every few months, depending on the level of water contamination, to clean the filter. Otherwise, if everything goes according to plan, there is usually no reason to open the solenoid valve box during normal operation.

Dig a Hole

The hole for the box should be slightly deeper and significantly longer and wider than the outer dimensions of the box to allow space underneath for the gravel fill and sufficient space on the sides to guide the supply line and the pipeline outlets to the zones. Allow about 2 to 4 inches at the bottom, and at least 8 inches around the box.

Fill with Gravel

Ideally, you should place a weed barrier in the area under the box to prevent weeds from growing through from below. Then, add about 2 to 4 inches of coarse gravel to prevent rainwater from stagnating in the box, instead draining away quickly. The gravel is then compacted to prevent the base from giving way.

Insert the box

The box is then positioned so that it is level, there is enough space on the sides for the connections, and its lid sits slightly above ground level, about 0,5 inches. This way, it is not visible in the lawn at first glance and can be safely driven over with the lawnmower. The slight protrusion above ground level prevents softened soil from being washed onto the box during heavy rainfall.

Box positioned in the hole

Connect the pipeline

Now, the connector at the box inlet is connected to the supply pipeline leading to the water source, and the pipelines supplying the individual irrigation zones are connected to the outlets. As always, the following applies here: Use as few connectors as possible to avoid unnecessary pressure loss! Therefore, only use 90-degree connectors (L-pieces) if they are absolutely necessary due to the space available. If conditions permit, it’s better to simply route the pipeline in a wide arc around the bend.

It can’t hurt to color-code the different pipeline ends leading to the irrigation zones, e.g., with differently colored insulating tape. This makes it easier to distinguish which end of the pipeline belongs to which zone when connecting, and you don’t have to figure it out by trial and error.

Test the connections for leaks

I would perform this step before connecting the irrigation computer. Common solenoid valves allow for this by allowing manual opening of the valve. If that’s not possible, this step is only possible once the control system is connected.

To do this, activate the water source and then open and close the individual solenoid valves one after the other. This is done by turning the solenoid valve coil a quarter turn in the direction indicated on the valve.

After opening, carefully check each zone to ensure that no water is leaking at any of the connection points inside or outside the box. Once everything is sealed, you can proceed to the next step.

Connecting Solenoid Valves to the Irrigation Computer

Two wires lead from each solenoid valve. One of these wires must be connected to one of the zone outputs of the irrigation computer. These are usually labeled with numbers, so for an irrigation computer with six zone outputs, for example, these are labeled “1” through “6.” The second wire must be connected to the COM port of the irrigation computer. It doesn’t matter which of the two wires goes to the zone output and which to the COM port. If it’s important that the zones follow a specific order, for example, a certain zone is number 1, then another zone is number 2, and so on, then the wiring must be done accordingly.

Since space would quickly become limited at the shared COM port if the wires from numerous solenoid valves were routed through it, these wires are combined beforehand and then connected to a common wire at the COM port. And since the wires leading from the solenoid valve aren’t very long (approx. 20 inches), an additional control cable is usually required to extend them to the irrigation computer.

These control cables are cables for low-voltage applications with a relatively small cross-section, but a larger number of wires, which can be purchased from irrigation retailers.

This is what a control cable looks like. In this case, it has 7 wires, i.e., for 6 zones.

When joining the wires, make sure they are watertight. Specially offered cable sleeves and grease caps can be used for this purpose. The following article provides a detailed practical example for connecting solenoid valves to the irrigation computer.

Fill the hole again

Now you should perform another test to ensure that the zones can be switched on and off correctly via the computer and that all connections in the box are still sealed. Then, carefully fill the remaining space around the box with soil. It’s best to dig it slightly above the soil level, as the soil will settle slightly over the next few days. Optionally, you can add some humus and sow grass seed, or reinsert a previously dug-out turf so that the area around the lid can quickly become regrowth.

Solenoid valve box fully installed

What alternatives are there to the solenoid valve box?

Under no circumstances is it recommended to bury the solenoid valves themselves – without anything around them – or to bury them in a box that is inaccessible from above or that is completely buried in the ground. In the first case, the valves are not adequately protected, and long-term functionality is not guaranteed. In the second case, if something malfunctions, you cannot reach the valves, or after a longer period of time, you may not even know where the valves are buried.

It is also no longer state of the art to place the valves individually in several locations in the garden. This used to be common practice to save on pipeline costs, but it brings with it disadvantages in operational handling that are far from offset by the comparatively small savings in material costs.

Wall Mounting

An equivalent alternative to placement in a valve box is a wall-mounted system. The components included are practically identical to the internal components of a solenoid valve box, but they are mounted in such a way that the system is suitable for wall mounting.

The advantage over a solenoid valve box is a comparatively lower price and easier installation. The disadvantage is that the valves cannot be elegantly concealed underground; instead, they are visible from the outside. This may not be a problem if the wall bracket is installed in a location that is not or hardly visible from the outside, or in a separate utility room, but in other cases it could make the garden look a bit cluttered.

Example of a valve distributor set suitable for wall mounting (Image: DVS Irrigation)

Automatic Water Distributor

An automatic water distributor is a way to do without solenoid valves altogether. This solution doesn’t work quite as professionally as a solution with solenoid valves, but it is significantly less expensive. Currently, the only product in this segment is the Gardena Automatic Water Distributor. It has 6 zone outputs and operates without electricity, instead using the pressure of the flowing water to switch from one zone output to another.

Gardena Automatic Water Distributor

For this to work, you need a different type of irrigation computer than the one used for switching external solenoid valves—namely, one through which the water flows. And its software must be compatible with the automatic irrigation computer; I explicitly point this out in the following irrigation computer comparison.

Irrigation Computers with Multiple Outputs

Theoretically, it’s even easier to use an irrigation computer with multiple outputs. Models with 2, 3, and even 4 outputs are available on the market; with the Orbit B-Hyve XD and the LinkTap Q1, there are even smart models with 4 outputs that can be controlled via the web.

Orbit B-hyve XD Irrigation Computer with 4 outlets

Should you buy a ready-made solenoid valve box or assemble it yourself?

Building it yourself is basically quite possible; all the necessary components are also available separately. The challenge is, on the one hand, to ensure everything is properly sealed and, on the other, to make the box compact enough to avoid taking up too much space in the garden.

You can only save a limited amount by building it yourself: Ready-made solenoid valve boxes for 6 zones cost around $400 to $500 in stores, with the cheapest options starting at around $300. Six solenoid valves alone cost around $150. A large empty jumbo valve box costs $70 to $100. Three valve manifold crosspieces cost around $25, and the seven required PE pipe connectors cost around $35. This brings the material costs to around $300, and that doesn’t include a filter, compressed air connection, ball valve, or moisture-proof box. These add up to another $80 to $100.

Ultimately, a maximum saving of $100 seems possible, but it involves a lot of effort and the risk of having to deal with leaks or purchasing incorrect components that don’t fit together properly. In my experience, DIY construction isn’t really worth it in this area. I would only recommend it if you need a solution outside of the standard range, e.g., because space isn’t available, or if it’s important to you to install very specific components in the box.

What should you look for when buying?

There’s a wide range of pre-assembled solenoid valve boxes on the market, some from well-known brands like Rain Bird or Hunter, and some from no-name suppliers. And some are also hybrids, e.g., no-name pipe connections and housings combined with branded solenoid valves from Hunter.

Brand or no-name?

My tip: I would advise against completely no-name products in this area, as the product quality is questionable and you run the risk of purchasing a product that is unreliable in everyday use and potentially causes a lot of trouble. However, I think a hybrid, where the essential components like the solenoid valves are from branded manufacturers, but the rest of the components are partly or entirely no-name, is worth considering. This could save you a few hundred dollars or more compared to a 100% branded product. In such a case, I would just pay special attention to ensuring the housing is sturdily built. Some boxes are offered that look quite delicate, and I have doubts about whether they’re even suitable for driving over them. The option with the lowest risk is obviously to go for the complete branded product.

Number of Zones

The first selection criterion is the number of zones you want to supply with the valve box. The box must contain at least that many solenoid valves, although it never hurts to have one or two zones in reserve in case you want to expand or modify something. Solenoid valve boxes aren’t available in any size; the largest I know of are for 10 zones, but usually they top out at 6. If you need more, you’ll have to install multiple boxes.

Direct or alternating current

Depending on whether you’re using a water computer with a power connection or a battery-powered water computer, you’ll need a box with 24-volt alternating current (AC) or 9-volt direct current (DC) solenoid valves. Most of the models available are 24V valves.

Size of the inlets and outlets

Boxes are available with 1-inch or 3/4-inch inlets and outlets, some packages allow you to select the size variable at the time of purchase. Ideally, you should buy a box that matches the planned connection sizes. So, if you have a 1-inch supply line, choose one with a 1-inch connector on the inlet side, and if you’re using a 3/4-inch pipeline on the zone side, choose one with a 3/4-inch connector on the outlet side.

Included extras

If you haven’t planned a drain valve or a deep-seated ball valve in your irrigation system for frost protection, then a compressed air connection included in the box is mandatory. In conjunction with the compressed air connection, a ball valve on the inlet side is a great advantage, as it makes it very easy to avoid the compressed air blowing toward the water source.

A filter is also required if you haven’t already planned for one elsewhere. This is even more important if you are also operating micro-irrigation zones.

A damp-proof box is also perfectly fine; it simplifies the initial installation. Alternatively, you can easily make the waterproof connections yourself using suitable accessories.

Der Beitrag Why do you need a solenoid valve box, and what are the alternatives? erschien zuerst auf Irrigation Blog for Do-it-yourselfer.

In this article, I’ll show you how to adjust the sector to be watered and the throw distance for Gardena sprinklers from the T-series, SD-series, MD-series, and OS-140 rectangular sprinkler.

These series currently include the following models:

• T Series: T-100, T-200, T-380
• SD Series: SD30, SD80
• MD Series: MD40, MD80, MD180
• OS-140: Available in only one model version

I also provide information on the best settings to make on the sprinkler before use, to avoid any wet surprises when adjusting the settings, for example, to prevent accidentally watering sensitive areas in the garden or giving your neighbor a cold shower. This allows even inexperienced users to adjust the settings without hassle or stress.

Gardena T-Sprinkler

The settings for the three T-sprinklers differ for the T-100 and the T-200/T-380 models.

Gardena T-100

Preparation (before turning on the water supply)

The T-100 sprinklers are factory-set for 360-degree full-circle irrigation. This can be recognized by the black adjustment arrow on the orange rotating sleeve pointing to the full-circle symbol below. Turning the orange sleeve counterclockwise reduces the area of the circle to be watered. To set the maximum possible reduction, turn the sleeve to the white line. The area to be watered is now only 70 degrees, i.e., smaller than a quarter of a circle.

By turning the gray piston, the entire sprinkler can be rotated; the sprinkler makes a rattling noise. If you turn it so far that the semicircle symbol points toward you, the sprinkler will spray away from you.

Activate the water supply

Now turn on the water supply; the spray pattern should now look something like this.

Adjust the sector to be watered

The left starting point of the sprinkler, i.e., the point up to which the sprinkler waters on the left side, is determined by grasping the entire sprinkler by the gray piston and twisting it, as described above.

If the left starting point is correct, you can adjust how far to the right the watering should extend by turning the orange sleeve clockwise, thus determining the size of the circular section to be watered. The further you turn clockwise, the larger the circular section is. If you turn it to the maximum possible point, the sprinkler will water a full circle.

Note: Turning the gray cap at the very top of the nozzle has no effect on the irrigated sector. Even if the cap is turned, the previously set area will continue to be watered.

Adjusting the Throw

By turning the orange screw located in the riser, you can reduce the water flow and thus shorten the sprinkler’s throw. It is best to use a screwdriver for this.

Gardena T-200/T-380

These two sprinklers are adjusted in the same way; I’ll demonstrate this using the T-200 as an example.

Preparation (before turning on the water supply)

Since this type of sprinkler delivers a very concentrated water supply, it is sufficient to prepare by turning the sprinkler nozzle away from you and toward the sector to be watered. This is done by turning the thin plate at the very top of the sprinkler head so that the small white arrow points in the direction of the sector. The sprinkler will begin watering at the position of the arrow.

Activating the water supply

Now you can activate the water supply without getting wet. If you have sensitive terrain around the sprinkler that should not be sprayed with water, it is better to read the next section beforehand so that you can quickly adjust the sector setting.

Setting the sector to be watered

The section of the circle that the sprinkler should water is defined by turning the two orange rings located in the riser. The left sector limit is set with the upper ring, and the right sector limit with the lower ring. The line marking on the ring defines the point to which the sprinkler rotates left or right.

Note: If the sprinkler head is accidentally rotated in everyday use, this will not affect the sector setting; the sprinkler automatically returns to the correct sector setting. Gardena calls this the “memory function.”

Nozzle Selection

There are four nozzles to choose from, each providing a different water flow. Nozzle 1 provides the smallest amount of water, and Nozzle 4 the largest.

The purpose of this nozzle selection is to enable coordination of the water flow rate (MPR) when operating the sprinkler simultaneously with other sprinklers that water different sector sizes in a single irrigation cycle. For example, if the first T-200 irrigates a full circle, the second only a semicircle, and the third only a quarter circle.

Since completing a full circle takes four times as long as completing a quarter circle, the irrigated area of the quarter-circle sprinkler would receive four times as much water in the same time as that of the full-circle sprinkler, resulting in completely uneven irrigation.

This can be compensated for by using different nozzle sizes. These should be used as follows:

• Nozzle No. 1 – Quarter Circle
• Nozzle No. 2 – Semicircle
• Nozzle No. 3 – Three-Quarter Circle
• Nozzle No. 4 – Full Circle

The nozzle is selected using a screwdriver by moving the arrow imprinted on the orange screw to the desired nozzle number.

Adjusting the throw distance

The throw distance can be reduced to 5 meters. This is done with the adjustment screw located above the nozzle. Turning it toward the minus symbol decreases the throw distance. Turning it back toward the plus symbol increases it again.

Gardena SD Sprinkler

The two SD models, SD30 and SD80, use the same adjustment method.

Gardena SD30/SD80

Preparation (before turning on the water supply)

By turning the turquoise adjusting ring on the black nozzle counterclockwise as far as possible, you reduce the area of the circle being watered to the smallest possible size of just 5 degrees. The adjusting ring can be turned about 1 1/2 turns until it stops.

Then, turn the sprinkler on the black riser so that the arrow on the adjusting ring points away from you in the direction you want to water.

Activate the water supply

When you activate the water supply, the sprinkler will spray in the direction of the arrow. Since the irrigation sector has been reduced to the minimum, only a single jet will initially emerge from the sprinkler.

Setting the sector to be watered

To do this, first turn the sprinkler on the riser as far to the left as you want the sprinkler to spray to the left. Then turn the turquoise adjusting ring clockwise as far as you want the sprinkler to spray to the right.

Adjusting the throw distance

The throw distance is adjusted by turning the screw in the adjusting ring. Turning it counterclockwise decreases the throw distance. With SD sprinklers, the throw distance can be adjusted significantly. If you turn it far enough to the left, you can even turn off the irrigation completely.

Warning: Do not loosen the control screw too much, otherwise the sprinkler head will come off!

Gardena MD Sprinklers

The MD sprinklers are currently the most modern Gardena sprinklers and, along with the OS-140, the only ones that can be adjusted completely without tools. The adjustment process is the same for all three available models MD40, MD80, and MD180.

Gardena MD40/MD80/MD180

Preparation (before turning on the water supply)

The area to be watered is reduced by turning the adjusting ring on the nozzle counterclockwise. After approximately 3/4 of a turn, the adjusting ring is in place and the circular section is reduced to a minimum of 80 degrees.

Now, turn the sprinkler head on the black riser until the small black arrow on it points away from you in the direction to be watered.

Activate the water supply

After watering has started, the spray pattern will look like this.

Adjust the sector to be watered

You can determine how far to the left the sprinkler should water by turning the riser to the left. You can determine the right point by turning the adjusting ring to the right. If you turn it as far to the right as possible, a full circle will be watered.

Adjust the throw

On MD sprinklers, this can be set without tools using the turquoise ring located in the riser. This can be turned up to a quarter turn. To the left, it decreases the throw, to the right, it increases it.

Note: Especially with the MD40, you’ll barely notice any difference at first glance; only a very slight adjustment of the throw distance is possible. The effect is more noticeable with the MD80 and MD180.

Gardena OS140

Preparation (before turning on the water supply)

With this sprinkler, this first step of preparing the sprinkler is particularly important, as it has a fairly large operating radius when fully turned on, posing a significant risk of inadvertently splashing water-sensitive items, yourself, or other people. Without first restraining the sprinkler, it is virtually impossible to adjust it without getting a shower.

To adjust the sprinkler, first unlock the two latches on the cover and remove it. The cover should only be replaced at the very end, as otherwise it would be difficult to reach the necessary adjustment points.

If you now pull the sprinkler out of the housing, you will see the orange adjustment mechanisms for the sector to be watered, the throw distance, and the throw width:

3 Adjustment mechanisms for the OS-140

The most important preliminary step is to reduce the water supply to the minimum using the orange dial. This allows the sprinkler to start with the shortest possible throw distance, allowing you to then work your way up to the appropriate throw distance. To do this, turn the adjustment wheel approximately 1/4 turn to the right until it stops.

I also recommend setting the throw width to the minimum initially. This is done for both sides using the orange sliders on the left and right.

Finally, grasp the sprinkler head and rotate it in the desired direction. The area to be watered is limited by turning the wheel on the side closest to you as far up as possible. Turn it so that the bar-shaped mark on the wheel is almost at the top.

Activate the water supply

After watering starts, the water will initially trickle weakly from the sprinkler, and due to the lack of water pressure, it probably won’t move yet.

Setting the irrigated sector, throw distance, and throw width

Now, slowly increase the water pressure on the orange wheel so that the sprinkler head begins to move. First, for the side facing away from you, turn the adjustment wheel and further increase the water pressure to determine the point to which the sprinkler head will swivel and how far in that direction the sprinkler will irrigate. At the same time, use the two slide controls to set the desired throw width.

It’s important to work your way up gradually until you find the best setting, as both the throw distance and the throw width respond to the set water pressure.

Then, in the same way, set the turning point for the side closest to you using the second adjustment wheel. During this step, you may need to step back a bit to avoid getting wet, as the sprinkler may now be watering overhead.

Once all settings are correct, you can finally replace the cover.

Der Beitrag How to adjust Gardena sprinklers (T-series, SD-series, MD-series, OS-140 sprinkler) erschien zuerst auf Irrigation Blog for Do-it-yourselfer.