Reasons Why Your Irrigation Zone Is Not Coming On

Spring is fast approaching and soon it will be time to do the annual start-up of your irrigation system. It is always a good idea to have a professional do your start-up and audit at the beginning of spring. The Irrigation Tech will know how to trouble shoot any problems that might arise, fix any leaks, adjust heads as needed, and alter the program.

I am a do it yourselfer, so I understand that many homeowners like to tinker with their irrigation system and probably have been doing it for years. If you are one of those people, then this post maybe useful if you run into issues with starting individual zones.

Tip: Once you have ensured that there is power going to your clock, go ahead and change the back-up battery if it is an older style clock. This will keep it from losing the program during a power outage.

If your system was properly winterized, the next step is to turn on the main valve, or irrigation isolation valve. Usually, it is close to the water meter and it separates the irrigation line from the house supply line. Make sure to turn the valve on slowly, sometimes their can be extra built-up of pressure that can blow pipes apart if there is no pressure regulator installed. Walk around all areas covered by irrigation and look for any obvious signs of a leak, such as a geyser, water bubbling out of the ground, water running down the driveway or street, and water seeping from a head. Repeat this process once the startup is completed, often it takes a while for a leak o manifest itself.

Great, no obvious leaks, it is time to start the audit zone by zone. As you start activating each zone, looking for leaks in the individual zone lines, broken heads, broken or clogged nozzles and making any adjustments, you have a zone that will not come on at all. I usually make note of the particular zone and continue the audit. I want to make sure that it is only one zone. If it is, this will typically rule out the motherboard of the clock or a bad module (if it is an expandable clock – one you can add additional modules to if you need to add extra zones to your irrigation system).

You have now been through all your zones and you have one that is not coming on. Before you start troubleshooting, attempt to get the zone going one more time using the manual start through your clock. If the problem persists, it is usually an indication of an electrical problem. If you know where that valve is located, you can open the valve manually. If the zone comes on, then it is an electrical Issue. At this point, if you have no experience with electricity or plumbing, I recommend calling a reputable irrigation company. The two main culprits are usually a cut/damaged wire or bad solenoid.

Reason #1 Bad Wire

You can check the wire by disconnecting the hot and common wire from the solenoid and test the voltage coming from the clock.

  • If the voltage is between 22-28 volts, this is a good indication it is not the clock and the wire is intact.
  • If you have low voltage, this is a good sign that there is a nick in the wire, and it is contacting something, or the wire is damaged, but not cut all the way through.
  • If you have no voltage, then this is a good indication that the positive wire is cut. It could be the common wire close to the valve, but unlikely. Typically, the common wire is daisy chained together from valve to valve. A broken or damaged common wire would be part of your trouble shooting exercise if you have issues with all or more than one zone not activating.

Should you have a broken wire, call your Irrigation Tech, have them to come out, do a wire trace to find where the break is and make the splice.

Ok, your voltage is good so what else could it be? It might be as simple as a bad connection. Cut, strip the wire, and reattach them to the solenoid. Reactivate that zone trough the clock. If it comes on, you found your problem, if not, then most likely you have a bad solenoid.

Reason #2 Bad Solenoid

It takes specialized equipment to test a solenoid. I would once again recommend calling your Irrigation Technician rather than attempting this repair yourself. A new solenoid for that brand, model of valve will need to be ordered and installed.

I hope you found this information helpful. Keep in mind, this post is not meant to be an exhaustive problem-solving guide to all irrigation related issues, as I have not yet touch on how to determine if you have a leak, how to troubleshoot a leak, or how to fix a weeping valve. Those are posts for another day. Too technical, don’t have the tools, or the time to mess with it? Not worth a headache or an argument with your significant other because there is another incomplete project in the household? Give us a call, we will take care of it for you.