Zone not working properly

[alsfan]

I have 4 zones that were installed last year. They were all working properly until about 3 weeks ago. 1 zone seems like its not getting full pressure, the heads won't pop up completely and when I pull them up, they drop back down. There is no leak and I blew out the valve and replaced the diaphram and solinoid filter but there is no change. Yesterday I turned it on manually and it worked 1 time until I turned it off and then it hasn't worked again. Any suggestions would be appreciated, thank you

[Waterbringer]

An odd set of symptoms. . .now that the low-pressure issue has been eclipsed by the fact that the valve is seemingly not working at all, lets start with that, as the they might be two separate issues entirely. Whenever I hear that a homeowner has 'worked on' a valve I wince, as the result is usually that the owner is worse off than before, as working with 0valves is a tenuous endevour at best.

(If you know what a flow control is and already ruled it out, skip the following paragraph. . .)

Anyway, one of the first things I check is the flow control, if the valve has one. I don't know what make/model your valves are, but as flow controls can be used to manually activate a valve, often owners will play around with it and end up permanently shutting off the valve (ie, it won't electrically be able to override the closed flow control and open up). Flow controls are usually handles that spin and do indeed manually open/close valves but are primarily used to, well, control (or reduce really) the flow through a particular valve independently of the other valves. If you used it to open and close the valve manually, you may have screwed it down enough so that the valve is essentially sealed shut, hence its inoperability.

Otherwise, it would be odd that a valve would not work at all after being manually operated, and I'd move on to other tests to diagnose the issue. If this is the issue, then I would suggest ensuring that the flow control is open completely (careful here, some flow control handles can spin right off, as I said dealing with valves can be extremely tricky). If the low-flow issue was a different problem, chances are you will be back to where you started--operating valve, but low flow. I suspect the low-flow issue and the inoperability issue are separate, as one happened spontaneously and the other happened after work to a valve, but I could be wrong. Try this first and we'll go from there.

It would also be helpful to know what valve make/model you are using, as valves all have very very different personalities.

Good luck,
C