Hunter Sprinkler System Won't Turn Off Quick Troubleshooting Guide

Hunter Sprinkler System Won’t Turn Off: Quick Troubleshooting Guide

If you’ve ever experienced an issue with your Hunter sprinkler system not turning off, you know how frustrating it can be. This common problem can occur due to several reasons, and in this article, we will discuss them and offer some possible solutions to get your sprinkling system back on track.

One potential cause of a Hunter sprinkler system not shutting off is related to pressure requirements. The valves need at least 20 PSI to close properly. Moreover, the internal screws and levers around the main water valve can sometimes get stuck in the open position, which can prevent the system from turning off.

Perhaps you’ve encountered a faulty rain sensor that doesn’t interrupt watering when it should. Don’t worry, we will cover these issues and more in the subsequent sections to help you troubleshoot your Hunter sprinkler system and get it working efficiently once again.

Understanding Hunter Sprinkler System Components

Controller and Control Panel

The heart of your Hunter sprinkler system is the controller. This device manages the timing and duration of your sprinkler system’s operation. The control panel is the user interface, where you can program your system and make adjustments to watering schedules.

Sprinkler Valves

Sprinkler valves are the gatekeepers of your system. They control the flow of water to each zone within your sprinkler system. Valves can typically be found in underground valve boxes and are connected to the controller using cables.


Connected to the sprinkler valves are the solenoids. These are small, cylindrical devices with two wires coming out of them. They act as switches that open or close the valves, allowing water to flow through the sprinkler system when activated by the controller.

Diaphragm and Valve Diaphragm

Diaphragm and Valve Diaphragm

Inside each valve is a flexible rubber disc called a diaphragm. The diaphragm’s primary function is to control water flow within the valve. When the solenoid is activated, water pressure builds up under the diaphragm, lifting it and allowing water to flow through the valve.

If your sprinkler system isn’t turning off, it could be due to a damaged diaphragm. Inspect it for rips or holes and replace if necessary.

Sprinkler Heads and Zones

Your sprinkler system is divided into separate areas called zones, each with its own set of sprinkler heads. These heads are responsible for distributing water evenly across your lawn or garden.

Sprinkler heads come in various types and spray patterns, including pop-up, rotor, and spray heads. Make sure to keep these components clean and well-maintained for optimal performance.

Backflow Preventer

A crucial component for safeguarding your water supply is the backflow preventer. This device prevents contaminated water (from sprinkler runoff or other sources) from flowing back into your home’s potable water supply. It is essential to ensure that your backflow preventer is functioning correctly and regularly inspected.

By understanding these crucial components, you’ll be better equipped to diagnose any issues that may arise with your Hunter sprinkler system, including why it won’t turn off. Remember to keep each part well-maintained and routinely checked for optimal performance.

Common Causes for Sprinkler Systems Not Turning Off

Common Causes for Sprinkler Systems Not Turning Off

Debris and Clogs in the System

Debris and clogs can cause your sprinkler system to malfunction and not turn off properly. If there’s any obstruction in the system, water flow will be affected and the sprinkler heads may not close as they should. To fix this issue, be sure to regularly clean and maintain your sprinkler system by checking and clearing debris from the sprinkler heads and pipes.

Damaged or Malfunctioning Valves

A common cause of a Hunter sprinkler system not turning off is a damaged or malfunctioning valve. This can result from wear and tear or damage to the valve itself, causing it to get stuck in the open position. To resolve this, you may need to:

  1. Locate the problematic valve and turn off the water supply.
  2. Remove the valve and inspect it for damage or wear.
  3. Replace the valve if necessary, or clean and lubricate it if there’s no visible damage.

Issues with Solenoids

Solenoids are the electromechanical devices that control the flow of water through the sprinkler valves. If there’s an issue with your solenoid, your sprinkler system may fail to turn off. Here’s what you can do to troubleshoot solenoid issues:

  • Ensure that the solenoid is properly wired and connected to the controller.
  • Inspect the solenoid for visible damage or wear and replace it if necessary.
  • Test the solenoid’s function by turning on the system and checking if the valve opens and closes properly.

Sprinkler Controller or Control Panel Errors

Sprinkler Controller or Control Panel Errors

Your sprinkler controller is responsible for managing the entire sprinkler system, including when it should turn on and off. If there are errors or issues with your controller, your system may not turn off as expected. To address this:

  • Double-check the programming and timer settings on your sprinkler controller.
  • Reset the controller to factory settings and reprogram it as needed.
  • If the issue persists, consider upgrading to a newer, more advanced controller for better efficiency and control.

By taking the time to identify the common issues that can cause your Hunter sprinkler system to not turn off, you can keep your system running efficiently, save on your water bill, and maintain a healthy lawn. Remember, regular maintenance and checking for debris, valve malfunctions, solenoid issues, and controller errors are essential to ensuring a well-functioning sprinkler system.

Troubleshooting and Fixing the Issue

Troubleshooting and Fixing the Issue

Inspect and Clean Valves

When your Hunter sprinkler system won’t turn off, you should start by inspecting and cleaning the valves. First, turn off the main water supply using the shut-off valve or “off” switch on the controller. Then, expose the top of the valve and detach the valve diaphragm. Turn the water supply back on and flush out the valve for at least fifteen seconds. Examine the diaphragm for any rips, holes, or other damage. Remember that Hunter valves require at least 20 PSI to close, so ensure the pressure requirements are met.

Check and Replace Solenoids

Next, check the solenoid on the problematic zone. Use a multimeter to measure the solenoid’s voltage and resistance. If electrical specifications are outside the recommended range (24 VAC, 350 mA inrush, 190 mA holding, 60 Hz), the solenoid may be faulty. If you find a defective solenoid, replace it to ensure proper functioning of your irrigation system.

Reset and Test Controller

Sometimes, your controller may be causing the issue. Reset the controller by pressing the reset button or by unplugging the power supply and reconnecting it after a few seconds. After resetting, test each zone by manually activating it from the controller and observe if the sprinkler system turns off as expected. Make sure to check that the wire connections are good, watertight, and not undersized.

Monitor and Adjust Sprinkler Heads and Zones

Adjusting sprinkler heads and monitoring the zones in your system can also help fix the issue. Check for any misaligned or damaged sprinkler heads. If any are found, replace or adjust them accordingly. Additionally, ensure each zone’s settings, such as run times and scheduled days, are correct to prevent overwatering or constant running.

Follow these steps and your Hunter sprinkler system should be back to normal in no time. Remember that regular maintenance and inspection can help prevent these issues in the first place. Happy watering!

Locating and Using Main and Zone Shut-Off Valves

Main Shut-Off Valve Function and Location

The main shut-off valve is crucial in controlling the water supply to your entire Hunter sprinkler system. Usually, it’s located near the backflow prevention device or backflow valve. If you’re unsure where your main shut-off valve is, try looking around the main water line where it enters your property.

Zone-Specific Shut-Off Valves

Your Hunter sprinkler system will have separate shut-off valves for each zone, making it easy to control the water flow to specific areas. These valves can be found within the valve boxes, usually buried in the ground near the sprinkler heads. Within these boxes, you’ll find solenoids, which are cylindrical parts with two wires that control the opening and closing of the valves.

Types of Valves: Ball Valves, Gate Valves, and Irrigation Valves

There are different types of valves commonly used in sprinkler systems:

  1. Ball Valves: These valves allow you to control the water flow by turning a handle to open or close a spherical part within the valve. To shut off the water, simply turn the handle 90 degrees clockwise.
  2. Gate Valves: These require you to twist a wheel to open or close the valve. To close the valve, turn the wheel clockwise until it’s tight.
  3. Irrigation Valves: These are specifically designed for sprinkler systems and can be operated electronically, manually, or by a timer.

Here’s a comparison table of the three types of valves:

Valve TypeMechanismUsage
Ball ValveHandleEasy control
Gate ValveWheelPrecise control
Irrigation ValveElectronic/ManualSprinkler-specific

In case your Hunter sprinkler system doesn’t turn off as expected, try these steps:

  • For ball valves: Turn the handle 90 degrees clockwise.
  • For gate valves: Turn the wheel clockwise until it’s tight.
  • For irrigation valves: You can manually close them by twisting the solenoids clockwise.

Remember to keep all your valves in good working condition by inspecting and maintaining them periodically, to prevent any water wastage or damage to your landscape.

Preventive Measures and Maintenance

Regular System Flushing and Debris Removal

To avoid potential issues with your Hunter sprinkler system not turning off, regularly flush the system to clear any trapped debris. It’s common for dirt, pebbles, or dirty water to get lodged in the valve, preventing it from closing properly.

  1. Turn off the main water supply.
  2. Open the flushing valve or remove the sprinkler heads.
  3. Turn the water supply back on for a short period to flush out any debris.
  4. Reattach any removed parts and turn on the system to make sure everything works correctly.

Keeping the system clean will ensure that it works efficiently and lasts longer.

Checking for Mechanical Errors

Regularly inspect your sprinkler system for any signs of mechanical errors. This may include checking for leaks, damaged pipes, or faulty valves. If you identify a problem, address it promptly to avoid more significant issues and ensure the system turns off as it should.

Monitor Water Usage and Bill

Keep an eye on your water bill to identify any potential leaks or issues with your sprinkler system. A sudden increase in water usage might indicate that the system isn’t shutting off properly or has a leak. Detecting these problems early will help prevent costly repairs.

Managing Power Outages and Controller Batteries

Power outages can affect your sprinkler system’s controller, which could result in the system not turning off as planned. Have a backup plan in place, such as a battery-powered controller, so your system can operate during a power outage. Additionally, regularly check and replace the controller batteries to avoid any interruptions in functionality.

By following these preventive measures and maintenance tips, you can keep your Hunter sprinkler system in top working condition and avoid any issues with it not turning off. Remember to be proactive by regularly inspecting and cleaning the system, monitoring your water usage, and having backup plans for power outages.

Professional Assistance

When to Call Irrigation Contractors

While some sprinkler system issues can be fixed on your own, there are times when calling a professional irrigation contractor is necessary. Consider reaching out to a contractor when:

  • You have tried troubleshooting your Hunter sprinkler system, and it still won’t turn off.
  • The issue involves the water source, backflow prevention, or other components that require specialized knowledge and tools.
  • Your sprinkler system has multiple recurring problems that may indicate a more significant issue with the entire irrigation system.
  • You’re unsure how to diagnose or repair the problem and want to avoid causing more damage to your sprinkler system.

Choosing the Right Pro Contractors for the Job

Finding the right professional contractor to fix your Hunter sprinkler system is crucial to ensuring a timely and effective repair. Use the following tips to make an informed decision:

  1. Research and compare local contractors: Look for contractors who specialize in sprinkler or irrigation systems. Read customer reviews, compare prices, and verify their licensure and insurance.
  2. Ask for references: Reputable pro contractors will have no problem providing references from past clients. Reach out to them to ask about their experience and satisfaction with the contractor’s work.
  3. Get multiple quotes: Contact at least three contractors for estimates on the repair. This will give you an idea of the price range and help you choose the most cost-effective option.
  4. Check for warranties: Some contractors offer warranties on their work, which can provide peace of mind that the repair will be done correctly and last for an extended period.

To ensure your sprinkler system remains in top condition and to avoid any further issues, always seek professional assistance when necessary. Trusting a pro contractor with the job guarantees the best solution for your irrigation needs.


Q: Why won’t my Hunter sprinkler system turn off?

A: There could be a few reasons for this issue. It might be due to insufficient water pressure, as Hunter valves require at least 20 PSI to close. Another possibility is that the internal screws and levers around the main water valve might be stuck in the open position. Manually pushing them into the closed position should resolve the problem.

Q: What should I do if I suspect the valve is the problem?

A: Follow these steps to inspect and fix the valve:

  1. Turn off the main water supply using the shut-off valve or the “off” switch on the controller.
  2. Expose the top of the valve and detach the diaphragm.
  3. Turn the water supply back on and flush out the valve for at least fifteen seconds.
  4. Examine the diaphragm for any rips, holes, or other damage.

Q: How can I check if the issue is with my Hunter controller?

A: Verify that there are no multiple start times set up on your controller. This can cause the sprinkler system to run more than once a day. You can eliminate start times using the arrow buttons and finding the “OFF” option in between 11:45 pm and 12:00 am or midnight.

Q: My sprinkler system still won’t turn off after checking both the valve and controller. What should I do next?

A: If you’ve already tried the above troubleshooting steps, it’s advised to reach out to a professional technician or contact Hunter Industries directly for further assistance. Remember, it’s always better to seek help from experts when dealing with water and electrical systems.

Always keep safety in mind when addressing any sprinkler system issues. If you’re not comfortable troubleshooting your Hunter sprinkler system, consult a professional to avoid potential hazards.

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