# Valve won't open manually, but opens when another valve does



## DatCrazyMongoose (Jul 13, 2020)

Hello, everyone! I'm new here, and I've scoured the web looking for advice about a problem I'm having with my irrigation system. My controller is a Hunter X-Core 4 station indoor. Valves 1-3 are Hunter PGV-100JTs, and the 4th is a Rainbird low-flow (probably XCZLF-100-PRF). I also have a Hunter Rain-Clik sensor installed.

Now for my problem. For 3 years my newly installed system worked fine.This year after turning the system back on, I noticed a problem. Station 2 wasn't coming on when it should, but it would come on any time station 4 was running. I tried manually starting it on the control and by rotating the solenoid. It would not come on unless I turned on station 4, either at the controller or with the solenoid. I swapped the solenoid with station 3 (unused) and it still didn't work. I took the valve apart and didn't notice any blockages inside, and the diaphragm is in good shape.

I'm really at a loss here. It can't be electrical, and the mechanical parts look good. What else could it be? Thanks for any advice you can provide.


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## DatCrazyMongoose (Jul 13, 2020)

Here is a picture of my valves if it helps.


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## g-man (Jun 15, 2017)

The wires in the solenoid in the far left look to have an extra wire. Maybe it is a camera image optical illusion.


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## DatCrazyMongoose (Jul 13, 2020)

g-man said:


> The wires in the solenoid in the far left look to have an extra wire. Maybe it is a camera image optical illusion.


It must be an illusion. I'm pretty sure everything is wired correctly. I checked all the lines for shorts and opens with my multimeter, and everything checks good. I'm leaning toward a back pressure issue, but I was an aircraft avionics tech, not a hydraulics guy, so I don't know anything about that.


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## g-man (Jun 15, 2017)

Is the top right cap or thats the water indeed? The fourth line has a filter. If that's a cap, then they could be using the fourth valve as a master valve.

The valves open and close using the water pressure. The solenoid is there to control the water flow that makes the valve open or close.


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## DatCrazyMongoose (Jul 13, 2020)

Top right is the input from the backflow preventer, which is in another box to the right. From left to right, the valves are...
1) front left yard w/8 rotator heads
2) unused (future use will be a back yard drip system)
3) front right yard w/8 rotator heads
4) front garden drip system w/9 drip emitters


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## DatCrazyMongoose (Jul 13, 2020)

Tonight I'm going to swap the guts from inside the unused valve into the one that's not working and see what happens.


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## g-man (Jun 15, 2017)

I was going to suggest a swap to see if the problem moves. Check for rocks/debris when you take it apart.


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## DatCrazyMongoose (Jul 13, 2020)

I tore the valve apart again. I inspected and cleaned everything. I stuck a paper clip down the solenoid dump port and could see it come out the outlet section. I checked for debris. I swapped every component from an unused valve to the faulty one. No change. I'm just not sure what it could possibly be.


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## DatCrazyMongoose (Jul 13, 2020)

I swapped all the internal and external parts (solenoid AND bonnet) with two known good valves yet again. Still no difference. #2 valve refuses to open via controller or manually (bleed valve or solenoid twist). But it opens any time the #4 valve opens either via controller or manually (bleed valve or solenoid twist). I'm at a loss and getting ready to order a new valve, which could be a waste. I dunno. :dunno: :dunno: :dunno:


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## TSGarp007 (May 22, 2018)

DatCrazyMongoose said:


> I swapped all the internal and external parts (solenoid AND bonnet) with two known good valves yet again. Still no difference. #2 valve refuses to open via controller or manually (bleed valve or solenoid twist). But it opens any time the #4 valve opens either via controller or manually (bleed valve or solenoid twist). I'm at a loss and getting ready to order a new valve, which could be a waste. I dunno. :dunno: :dunno: :dunno:


At this point replacing all the valves wouldn't be a waste if it saves your sanity. When you say #2 valve opens anytime #4 valve is open, do you mean you can physically tell that water is now going through the #2 valve? 
Any chance at all the pipes are merged together outside the valve box (as crazy as it sounds)? What happens if you disconnect the #2 valve and run the #4 valve, does water still come out the #2 valve sprinklers, or out the pipe that was formerly attached to the #2 valve?


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## DatCrazyMongoose (Jul 13, 2020)

TSGarp007 said:


> When you say #2 valve opens anytime #4 valve is open, do you mean you can physically tell that water is now going through the #2 valve? Any chance at all the pipes are merged together outside the valve box (as crazy as it sounds)? What happens if you disconnect the #2 valve and run the #4 valve, does water still come out the #2 valve sprinklers, or out the pipe that was formerly attached to the #2 valve?


Yes, I can physically tell water is going through #2 when #4 is on. No chance the pipes are merged. It worked fine for 3 years. I haven't dug everything up, so I can't disconnect physically disconnect #2 valve.


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## RVAGuy (Jul 27, 2020)

I understand this sounds weird, but I believe a blockage in the manifold between valve 2 & 4 may be to blame (or between the inlet of valve #2 and inlet of #4). If #2 is coming on, it HAS to be from a lack of pressure by design.

If you are reducing pressure downstream of #4, by turning it on, the pressure downstream of the blockage may reduce and turn #2 on. Because of the blockage, pressure isn't quick to recover and the zone stays on.

You have a manifold that is easy to twist apart, so I'd give it a shot. It's free and will eliminate a backpressure concern. Just a fresh idea.


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## DatCrazyMongoose (Jul 13, 2020)

Thanks for that tip. I'll be sure to check that when I have it torn apart.


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## DatCrazyMongoose (Jul 13, 2020)

Well, here goes... I humbly apologize to everyone for wasting your time. It turns out that I DID cross the lines. Last year when I had my yard dug up to install a drainage line, I rerouted the sprinkler lines which made them a bit too short. Apparently, I reattached them backwards. Now, the reason why it wasn't apparent to me is that the #4 drip zone tees and one goes to each side of the house. The two line I swapped were the left half of #4 zone and the #2 zone. All the #4 emitters are hidden except one, which is on the right side of the house. I didn't notice that the other half wasn't on when the #4 valve was open. If I had noticed, my troubleshooting would have been different. I made a few incorrect assumptions along the way, and my lesson is learned. Thanks for your help and guidance.


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## g-man (Jun 15, 2017)

I'm glad you figure it out.


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