RO auto shut off valve keeps cycling on and off

[tygunn]

I finally got my 90g tank and sumo filled tonight. As I was coiling up the rodi lines I noticed the waste line started trickling a bit, and the auto shutoff valve started softly humming. The water started trickling more and the hum got louder until all of a sudden the water stopped and the humming stopped. This keeps cycling.

I am guessing I need a new auto shutoff valve?

Tried using up a bit of water, shutting off the tank, etc.

 

[sjbro]

If the valve shuts off the water and then it starts again, it could be that three is a small leak in the clean water circuit. The leak makes the pressure drop, then the valve opens to refill the clean water, the pressure goes up, the valve closes, and the cycle repeats.

 

[tygunn]

That's a good point. It was dark when I was poking around in the RO/DI cabinet outside, so I might have missed something leaking. I'll take another look in the light today. Guess I should also check the water pressure too just to ensure that is within spec.