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Starting Member

Posts: 1

Location: Minnesota


Tuesday, August 7th 2018, 9:39pm

VAC to zones, Solenoid and Valve works, but not with certain wires...

Hello, this is my first post as I've hit rock bottom of my troubleshooting skills apparently. I will describe my problem as effectively as I can.
I have an 8 Zone system with 3 boxes of in ground valves. Rainbird solenoids, Hunter heads and controller (simpler digital model). I don't know how my system may effect questions/answers so please ask away for more details.

Zone 1 and 2 won't turn on with the controller but Z3 does. Valves and Solenoids are all align with their zone, V1/S1/Z1, V2/S2/Z2, and V3/S3/Z3. All wires at the underground box have >24VAC.

I moved S1 and S2 to Z3/V3 and they all activated Z3 sprinklers successfully, so that proves that all solenoids are individually functional (right?). Note that S1 and S2 had a slightly higher resistance of 56 Ohms compared to S3's 46Ohms.

Now to check the valves/diaphragms (my most unfamiliar topic) I figured I would put Z3 wiring to S1/V1 and S2/V2 which they all activated successfully.

This is where I am confused because I verified the solenoids and wiring is ok yet it doesn't point to anything specifically. The only last information I can offer is that Z3 is at 27VAC and when it is running it drops to 25.3VAC. When I do the same measurement to Z1 or Z2 (with their original valves and solenoids), I read ~26V at the wires and then when they solenoid is connected, it drops to 0-2V and doesn't activate. This is the most curious thing I can mention but can't say I know what it impacts.

I've re stripped wires and tried different wire nuts. I even grabbed 2 different extra wires (red and green) and ran those for Z1 and Z2, however I couldn't get any voltage reading like those extra wires I selected and tries using were open circuit.

My questions beyond any suggestions would be:
1. If I use the manual valve thumb screw, does that prove the valve diaphragm is ok?
2. If a solenoid reads slightly high resistance, could it not activate because its voltage drop is too much for the 27V?
3. If I can get 26V from Z1 and Z2, is there any other way the wires may be bad?
4. Why don't 2 randomly picked extra wires used get voltage to the box, Suddenly Z1 Z2 and these extra wires are corroded? Seems odd. Z1 also just recently stopped working within the last month.

I'm a first time homeowner, young mechanical engineer with a good DIY mind so anything would be appreciated! The irrigation place screwed me over last year and wanted $400 to repair all my leaky heads when I did it for $40, so I'm addicted.

This post has been edited 1 times, last edit by "UffDaDan" (Aug 8th 2018, 5:38pm)

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