One of the most common reasons for a station to remain on while cycling through other stations is the valve is dirty, occasionally it can be an electrical issue or simply mechanical damage (ie squashed by a car), both topics I intend to cover in subsequent posts.

The most common reason, and the reason we shall cover today, for a valve to remain on, or weep, is dirt or calcification trapped in the insides of the valve.

There a few causes for this annoying outcome:

• An initial installation that was completed without properly flushing the system.

• A recent mainline repair, again without proper flushing.

• A property with poor quality bore water, bore water can contain debris and particulates which make their way into the valve body. 

The resolutions to these issues is the same and outlined below:

Ensure that you SHUT OFF the main water supply. There is a high potential for injury from the stored pressure in the system, please also release the bleed screw prior to opening the valve.

• Locate the solenoid on the valve (a cylindrical object with two wires emanating from within. Check that the plunger is free from dirt & build up and check that it moves freely. When energising the station at the controller this plunger should freely retract.

• Dependant upon the make and model of your valve you will need to either unscrew the jar top or remove the bonnet screws to gain access to the interior of the valve. Note that the interior contains a spring loaded diaphragm that you should make an attempt not to lose.

• Check the diaphragm and spring for any obvious damage or deformation. The diaphragm should be clean and free of wrinkles, tears, or perforations. The seal should be clean and free of nicks, dents or abrasions. Wash the diaphragm, spring and seat in a bucket of dish soap to remove any build-up.

• Rebuild the valve and test the system.

Looking for more information on Re-Building Valves? Check out HOW TO RE-BUILD AN IRRIGATION SOLENOID VALVE for more information.

If you have completed all of the above and you still have a faulty valve, it will most likely need replacing or an electrical evaluation.

Model: Irritrol 40mm 216 Series Solenoid Valve With Flow Control