Sprinkler system issues


Old 05-24-10, 03:16 PM
Thread Starter
Join Date: May 2010
Location: USA
Posts: 2
Received 0 Votes on 0 Posts
Question Sprinkler system issues

Hi all,

I have a 8-station autmatic system and two of the stations are doing something a bit strange and have been doing so since I bought the house 6 years ago.

When I turn on station 3, station 6 also comes on at about 1/3 the normal pressure, wasting water. Likewise, when I turn on station 6, station 3 will come on at about 1/3 pressure. I have ruled out an electrical problem by disconnecting station 3 and turning on #6... the other one still comes on at reduced pressure.

I cannot figure out why this is happening or what can be causing it. It almost seems like there is some sort of internal connection between the pipes on the two lines but the fact that the other station comes on at reduced pressure is a bit baffling. I would think that if they were interconnected then they would always both come on at the same pressure no matter the station that you activate. Is there some sort of check valve or the like that can be causing this? There is nothing obvious and I have no idea where to look for something like this or if it is even standard.

I know nothing about sprinkler systems so need your advice here. Where do I look next to troubleshoot?

Thank you very much for your time!

Old 05-25-10, 01:53 PM
Group Moderator
Join Date: Mar 2003
Location: NC, USA
Posts: 24,418
Received 746 Votes on 685 Posts
How are the valves plumbed? I assume all the valves are installed in parallel (each is connected to the main supply line and each goes out to it's zone). I'm a bit stumped by why it only happens when that other specific valve is open.

Have you disassembled and cleaned the problem valves? Many use a type of servo system to open/close the valve. The electric solenoid opens a small port to allow water to enter the valve and move the main valve. Dirt can clog the passages preventing them from fully opening or closing. There could also be a worn seat or seal.

Another thought is that there is a bad connection or short between solenoids 3 & 6 with enough current getting through to partially open the valve. When you disconnected zone 3 did you do it at the control panel or at the valve? Disconnect at the valve to insure it is not getting any power.

This sounds like a fun problem. Make sure you post back when you get it solved.

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: