sprinkler valves

[djd]

I have a friend whom has a large property and 8 of his valves were not functioning ; all in the same line , about 300 feet from control source . The 8 out were all in line and at the end of feed . My first inclination was damaged wires underground . I isolated wires from valve on first of 8 closest to source and had no apparent short , brought power to that valve isolated from valve and had 26 volts . Once I connected the valve voltage went down to 3 volts . I swapped a working valve and the same thing happened ?? I`m lost next step relocate power supply with new wire . any insight .

 

[Sea Nile]

Easiest test I can think of without buying 300' of new wire is to unplug the source and bring it over to the valve. Either by running a bunch of extension cords or a supplying power via a small generator. Then you can test the source on the valves with a short scrap of wire. If it works, then you must have bad wire in the ground.

If it doesn't work, you got a bad source

I assume the source is a rain bird style control panel

 

[djd]

It`s A rachio app control , his whole house is automated , the sprinks are separate . I get voltage , not short to ground , a real ?? . We have wire It just doesn`t make sense , if the wire ho am I getting 26 volts , and all 8 doing the same thing .

 

[djd]

I`m in San Diego may be familiar, worked on the bases here can`t count him all

 

[Sea Nile]

You have voltage, but do you have amps?
If you connect 8-AA batteries in series you get 12v DC but you can't crank a car with it, if you try it will probably drop to 1V or less.

I suspect it's the source.

 

[hbiss]

Agreed.

-Hal

 

[hillbilly1]

Have you tried a different zone output? Sounds like a bad output since the working replacement does not work either. (Assuming this worked at one time)

 

[Wattman]

Disconnect the cable and read resistance of each conductor back to the source. Sometimes there are spare unused conductors put two together and verify on the other end.

 

[hbiss]

Have you tried a different zone output? Sounds like a bad output since the working replacement does not work either.

A knowledgeable troubleshooter would check the voltage directly at the output of the controller while the zone is activated. 3 volts there would indicate a problem with the controller.

You could also temporarily remove the zone wiring from the controller and connect it directly to the 24 volt transformer powering the system to see if it works then.

-Hal

 

[djd]

thinking the same

 

[djd]

Agreed.

-Hal

the wires were the problem , the short or damaged wire would only show up under load . This was a good lesson .

 

[djd]

Have you tried a different zone output? Sounds like a bad output since the working replacement does not work either. (Assuming this worked at one time)

That was done , when I did that , I had correct voltage and and no short between the two wires . only under load did I read 3 volts. Replaced wires and everything worked fine .