Tuesday, April 15, 2008

Sprinkler System Wiring Problems

I got this email from Johnny:

Hi Craig,
I really hope you put out a electrical wiring troubleshooting DVD soon! I could really use it right now.

On the phone you gave a quick troubleshooting wiring run-down but I can't remember what the heck you told me.

I have a house that has a problem with the sprinklers coming on . They just stopped all of a sudden. Its a new home with a Hunter Pro-C and 10 Hunter ASV 1" valves. The Controller is on the outside of the house.

I am getting a message on a Pro-C that says "1 err, 2 err, 3 err, 4 err" etc.
I get this when I try and put it through manual mode.
All connections looks good on the outside at the valves.

I took my volt tester and there is power coming in and the transformer is working. I don't think there is a broken wire. Its a brand new home.

How do I troubleshoot the wiring to find out where there is a short or faulty solenoid on specific valves and station wires?

I really appreciate any help on this. Thanks.


Well Johnny, not all irrigation installers do good work. I often find problems on new homes.
Because all the valves are reading "Error" we can assume the
sprinkler valve solenoids are not the problem. The chance that four new valves have shorted solenoids is astronomical. Somewhere there is a sprinkler wire short circuit. If a wire was broken you would not get an "error" message. "Error" means a short. In a controller using fuses, the fuse would be blown and the digital display would be blank (as in Rain Bird ESP controllers.)
This is a situation where your ohm meter is your best friend. A good circuit will read 20 to 60 ohms. Rain Bird solenoids will read in the mid fifties.
I would look in the easiest place first. Open the controller panel first. Is the common wire shield scraped and touching another wire? Often when using multi-strand wire
(colored wires inside a black sheath) the common will get scraped and touch another wire while peeling back the sheath.
Next, look for that same problem at the valves. Are the valves wired correctly? My guess is that somewhere the common is touching another wire.
If none of that works, disconnect the common in the controller and and run a new common wire. If you have a spare unused wire in the controller, try using that as the common. You'll have to wire all the valves to it.
This is the best book I have ever read on the subject of
electrical troubleshooting sprinklers. "Troubleshooting Irrigation Control Systems" by Bill Derryberry. Get it at the www.irrigation.org bookstore.
You can also access lots of sprinkler system troubleshooting info in the power point and resources area at www.IrrigationTV.com.

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