You are not logged in.

Dear visitor, welcome to SPRINKLER TALK FORUM - You Got Questions, We've Got Answers. If this is your first visit here, please read the Help. It explains how this page works. You must be registered before you can use all the page's features. Please use the registration form, to register here or read more information about the registration process. If you are already registered, please login here.

zmin2001

New Member

1

Sunday, June 2nd 2013, 12:47pm

One of the sprinklers in a zone always on

Hi,

I have a weird problem with my 9 zone irrigation system which is over 20 years old. I happened only recently whenever I turn on a zone (any zone other than 3), one of the four sprinklers in zone 3 is on as well (not all the sprinklers). I understand there could be controller or cross wire issue if all the sprinklers in zone 3 start together with other zones. However, in my case, only one of the sprinklers starts with other zones. If I turn on zone 3, all 4 sprinklers in the zone start fine.

Does anyone have clue why this happens? I'm new to this forum and have only very basic knowledge able how a sprinkler system works.

Appreciate your help.

Thanks,
Min

Wet_Boots

Supreme Member

Posts: 4,064

Location: Metro NYC

2

Sunday, June 2nd 2013, 2:27pm

You need to service the zone valve that feeds the always-on sprinkler.

mrfixit

Moderator

Posts: 1,469

Location: USA

3

Sunday, June 2nd 2013, 8:36pm

I agree with Boots. It sounds like valve 3 has a problem.
There's a master valve yes?
Go turn on the master valve manually and see if that sprinkler doesn't come on.
I'm betting it does. That means there's a problem with valve 3.
--
You could disconnect the number 3 wire from the controller and see if you still have the same problem. If it cures the problem there might be a problem with the controller.

zmin2001

New Member

4

Sunday, June 2nd 2013, 8:43pm

Thank you for your advice.

I just wonder, if the zone valve is bad, why only one of the sprinklers is on when the zone is off and the others are on only when the zone is on? Isn't the zone valve control the on/off of all the sprinklers in the zone? In what scenario the malfunction valve can cause only one of the sprinklers in the zone fail to shut down?

Thanks.

Wet_Boots

Supreme Member

Posts: 4,064

Location: Metro NYC

5

Sunday, June 2nd 2013, 9:08pm

there is on and there is on - a slowish flow of water through a faulty valve might show itself by draining out of only the one lowest-in-elevation head in the zone

mrfixit

Moderator

Posts: 1,469

Location: USA

6

Sunday, June 2nd 2013, 11:31pm

Is it possible there's two valves wired together as number 3? One of the two valves only has one sprinkler on it?
Maybe they abandoned all the heads on that line but the one? They wired two together so there wouldn't be too much pressure for just one head?

Wet_Boots

Supreme Member

Posts: 4,064

Location: Metro NYC

7

Monday, June 3rd 2013, 8:06am

Also, there can be a mix of heads on the faulty zone. At a certain pressure, for instance, a mixed zone of Hunter PGP and I-20 heads will have only the PGP heads popping up.

Rate this thread