I discovered tonight that my sprinkler system is no longer watering. I checked the controller (Hunter Pro-C) with a voltmeter and there is definitely ~26 volts flowing for each zone. I tried to fire each zone manually from the controller but no action on any of them.

I wasn't the home's owner when the system was installed, but I found one of the valves in the yard (in the dark) and manually turned the solenoid and the sprinklers in that zone (4) began to fire.

I went ahead and opened the waterproof wire nuts and set the controller to fire that zone. The multimeter only showed .5 volts.

At this point, I'm thinking that I've got a cut wire somewhere? I'm guessing it would have to be the common since theoretically each zone has it's own other wire. Otherwise, wouldn't some of the zones work?

Some questions:
1. Could a bad solenoid on Zone 1 cause all the other Zones to fail? Based on the wiring I saw, I'm guessing not...

2. Do the zones typically share a single run of common? If so, does that mean that if there's a cut wire it must be between the controller and zone 1 (or else some of the other zones would run)?

3. Any suggestions on how to find the wire/cut or my other valves (for a guy who 5 hours ago knew little to nothing about sprinkler systems)?

4. How deep is the wire usually run? Any common patterns for where it's run? Should I expect it to run close to the foundation? Wondering if I nicked a wire while doing some landscaping in a flowerbed right up against the house.

5. Is it strange that when I set the controller to manually run zone 1, I see voltage, not just for common and zone 1, but also common and each of the other zones? For some reason, I was only expecting to see voltage for the zone that's active. When I turn the controller to "Off", all the zones go to 0 volts.

 

There is absolutely no "common" way to run the sprinkler cable.

You know where the controller is located. You should know where all the valves are located.
The cable doesn't necessarily need to run to zone 1 first.
Based on where the controller is.... where is the closest valve to connect. Check there first.

How are your valves grouped ?
You can see the colors of the individual zones and the common wire. Focus on the common wire connection at your valves.

If you have an open common between all the valves and your controller.... you will see voltage on all zones.

 

Hunter Controller provides 1 terminal for connecting the zone valve commons. The irrigation installer may run 1 or more common wires to each in-ground zone valve box from the controller. At each zone valve box, the zone valve common wires and the controller common wire(s) are wire nutted together using a waterproof wire nut.

If the zone valve box has 1 common wire from the controller, it can be continuity tested by running an external wire from the controller to the zone valve box. Connecting the installed common wire and the external wire at either end, an ohmmeter should indicate continuity at the other end if the installed common wire is not defective. This continuity check can also be done by temporarily lifting a zone valve control wire at the controller. I would only do this if the installer used the zone valve wire color once,

My guess is a poor common connection at the zone valve box. Undo the common wire nut, restrip the wires and redo the wire nut. Good luck.

 

Thanks for the help guys. I've walked the yard multiple times and I can only find one valve box (zone 4). Would it be unusual for the rest of my valves to be buried? Wondering if there was an issue on Zone 4 with the previous owner and so when they fixed it, they installed box?

If they are buried, and I was recently digging in a flower bed near the house, would you start to lean towards a cut wire vs a loose connection? If so, what's my best bet for tracing that down without spending a fortune?

Thanks,
Brian

 

Usually lawn irrigation systems don't fall under any building code so I am sure there are many variations with installation. Since the main water line must be plumbed to the zone valve, most installations have the zone valves in 1 or 2 in-ground boxes. I doubt your zone valves are buried versus in a in-ground box or boxes.
While there are instruments for tracking buried electrical wire, the cost/use for a homeowner is prohibitive. Better to contract a lawn irrigation service and have them identify the location of the zone valves. Good luck

 

I had recently dug up a shrub near the house. I decide to go back and gently excavate that area and sure enough I found two red wires with about a 6 inch gap between them. When I bridged that with some spare wire, the sprinklers run as expected.

Still haven't found my valve boxes, but at least for now I know where my issue is.

Anyone have strong opinion about best way to splice in the missing wire?

Thanks,
Brian