Broke My Sprinkler System Trying to Fix it

[Spta97]

Hi all,

I know nothing about sprinklers systems other than what I found on the internet last night so I am hoping someone can provide me some guidance. My old sprinkler system was bubbling at one of the heads when the system was off and I found that the cause could be a blocked valve. I opened the valve box and unscrewed the PVC valve cover and did not find any blockage. When I went to put it back on and turned on the water the sprinkler would not shut off.

I was thinking it was a faulty solenoid so I turned on each zone individually and heard a click as well as the water running through it. That lead me to think it was a bad diaphram so I took it apart again but it seemed fine (see pics below).

I took apart a second valve and now that zone won't shut off either so I'm sure I am doing something wrong. I put the diaphram and spring on the solenoid cap (the diaphram fit in a groove) and it still will leave the zone open no matter how much I tighten it down.

My theory now is perhaps the diaphrams were so old that once I removed the cap they no longer were able to maintain a seal but I am really grasping at straws.

Any thoughts on what could be causing the issue?

Valve Box

Valve Assembly

Solenoid

 

[hj]

There are several things which can cause your problem, but they all boil down to one of two things. Either water CANNOT fill the cavity above the diaphragm to push it closed, or the water is leaking out of the upper chamber so it cannot build up pressure. FINDING the problem is the hard part because you have to make several tests to isolate what is happening AND WHY.

 

[Sponsor]

 

[Spta97]

Thanks hj. Some additional information which may be of help:

1) Until I disassembled the valves they were working (sans the zone that was bubbling which led me to disassemble them in the first place).
2) Each of the valve covers has a bleeder screw on it. When I open that up water comes out and the zone turns on. This leads me to beleive that water can make it's way into the upper chamber (not sure though).
3) When the valve cover is removed, and I turn on the water shut off valve on the backflow preventer, water will gush out (so I am getting water pressure the the lower part of the bladder).
4) The bladder and spring appear undamaged.
5) The valve covers seem to unscrew without much effort (some need coaxing with channel locks) but when I screw them down I cannot get them sealed properly without using the channel locks. I initially thought I was cross threading them but that does not seem to be the case.

What further tests should I run?

 

[Jimbo]

This is one of those things you should not overthink. REPLACE the diaphragms. If that doesn't fix it, you can replace the whole head. Looks like Lawn Genie. Shoudl be able to get parts at Ace or HD.

Now, for the rest of the story:
> save yourself some grief and clean all the debris out of that valve box before taking things apart.
> I hope that you have backflow prevention somewhere on your system, as required by code.

 

[Spta97]

Jimbo - thanks for the advice. I wil bring the diaphram to HD or Ace and see if I can find a replacement and post my results.

Regarding the box I was thinking of digging out the dirt and putting gravel in there (large gravel so it doesn't get stuck in the heads) which would allow drainage. Is that a bad idea?

Yes, the backflow device is located inside (the one good thing about this crappy install as I had to put a new one in a few years back) and it is tested for operation by the water company once a year to ensure it is in working order...the water guy was impressed that I put it on myself and said I did a better job than most plumbers around here

 

[Teamo]

Regarding the box I was thinking of digging out the dirt and putting gravel in there (large gravel so it doesn't get stuck in the heads) which would allow drainage. Is that a bad idea?

That is a good idea. Dig out around the box and pull it out. Remove the dirt under the valves and put some landscape cloth in the bottom and fill it with gravel.

 

[Spta97]

Well I think I fixed it. I was unable to get an exact match on the bladders so I cleaned everything up well (good idea) and reassembled:

Everything seems to be working ok.

I'm going to get one of those mega boxes but let me know if there is another alternative:

http://www.amazon.com/Orbit-Sprinkl...1?s=home-garden&ie=UTF8&qid=1313186354&sr=1-1

 

[Spta97]

I've been rethinking my plan and looking for advice. If I use this valve box, which is the only one I was able to find that is big enough for all the valves, it will stick out of the ground about 6". My other option is to put two normal size valve boxes down.

In order to address this the original installer put one regular valve box for the 4 left valves and one of the round shut off box for the remaining two - leaving zero room to work on them.

What's my best option here? I feel like the top of the box should be flush with grade.

 

[Teamo]

If you want to get the box deeper you can either notch the sides of it and it will fit over the lines or you could remove the valve setup and dig the hole deeper. You would need to extend the feed to the valve manifold. As far as the boxes I would use either two large boxes or one jumbo and a large. The small round one is too small to work in as you have found out. I like to use pre made threaded manifolds so I can add extensions between each set of four valves and each set has its own box. Looks like you have a glued up pvc manifold that is home made which is fine but it is not fun when it comes to removing valves for servicing. Here is a link to a typical valve manifold.....



http://www.sprinklerwarehouse.com/Sprinkler-System-Valve-Manifolds-s/38.htm

 

[hj]

The easiest, and often cheapest, would be to buy a new valve and just use the top of it.

 

[Spta97]

The easiest, and often cheapest, would be to buy a new valve and just use the top of it.

hj - I think that is what I am going to do. I thought the issue resolved itself however I noticed that one of the lines was weeping again.

Can you tell me if the threads on my PVC valves would be the standard for any valve I buy? If so, is there a brand I should get?

Thanks..

 

[Spta97]

I tried a top from Orbit and it didn't work. The solinoid did not seem to be clicking when it was screwed on but was when I took it off. I ended up going to Lowes and getting a RainBird with the top that is held down by screws. As luck would have it this particular valve was screwed (not glued) onto the PVC so I just unscrewed it and put the new one in. It seems to have fixed it as I have not seen any weaping from that zone.

It got me thinking though, I wonder how hard it would be to replace all the valves and completely redo the sprinkler system? Even the wire is solid so I would like to replace that with thicker gauge stranded and perhaps replace my million year old valve controller. The other issue is the actual sprinkler lines need repositioning / replacing so I wonder if I am just better off waiting until I have time to dig up the lawn? The front coverage is good but the back is spotty at best.

Any thoughts on the best brand of valves to use would be appreciated (though I did like the RainBird).

Thanks!