2 out of 4 zones suddenly don't work

[Mikeaz]

I have an automatic system with 4 zones. Today I noticed that 2 of the four zones have virtually no pressure. I'm not a irrigation pro, just a typical handy homeowner who can intstall valves, sprinkler heads, timers, tubing, do minor repairs, etc.

No water pressure on two of four valves of a system that has been in use for years...was working recently, no pressure when run with the timer, no pressure when tryiing to operate manually.

Any help?

Thanks

 

[Kiril]

Pressure problems like that usually means a broken pipe or riser.

 

[Sponsor]

 

[Prashster]

When you say 'manually' do you mean running a single station through the controller? Do you have the provision to manually turn the valve on and off from the valve box?

If you leave one of the 'bad' zones on for 5-10 minutes, do you notice a pool of groundswell somewhere? That'd point to a puncture. However, it's unlikely 2 zones would be similarly punctured or clogged at the same time (unless it's the beginning of the season and yr turning on after the winter).

I also doubt that 2 valves would simultaneously go bad.

My nonpro instinct is that it's a problem in the electrical connections to the valves.

 

[Verdeboy]

If you've opened the valves manually and there's still no pressure, then you have either a mainline leak or a clog just upstream from the first zone that doesn't work. Usually, with a mainline leak, it becomes pretty obvious where it is. For a clog, you'll have to do some digging.

 

[Mikeaz]

By manually, I go to the valve and turn the solenoid and/or the bleed screw, not related to the sprinkler timer/control.

No winter here in Phoenix. Sounds like I should run one of the bad zones and then look for the wet spot, hopefully? Between the main line and the valves?

Only going to be 113 here today so not too excited to dig for a broken pipe, but it is what it is.

 

[Kiril]

I would look for broken risers first.

 

[Mikeaz]

When I manually open the valves there is barely any water pressure getting TO the valves and passing through the valves on the two zones that aren't working. Mostly Drip irrigation and a few sprinklers...I don't notice anything broken or puddling in those areas.

 

[Verdeboy]

You need to troubleshoot the main line that goes from the the last valve that is working to the first valve that is not working. That means doing some digging.

 

[Rancher]

When I manually open the valves there is barely any water pressure getting TO the valves and passing through the valves on the two zones that aren't working.

Are all four zone/valve on the same supply line? Perhaps there is a valve to these two zones that someone have closed. I'm keying on your quote "TO".

Rancher (Sierra Vista)

 

[Mr_Pike]

Are all 4 valves in the same box and on the same manifold?

Can you describe your system in a bit more detail?