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Dema valve?

J

Jimmy Buffett

Active member
I have a ss bay where the water occaisionally just runs on it's own with about 10 lbs. of pressure. The logical culprit is the Dema valve, right?
Thanks
 
I only know of the Dema valve right by the pump. Is there another one?

I do have a weep system but this is considerably more pressure than weep. Could it still be weep?

Thanks
 
The first thing I would do is shut off the valve coming from your RO storage tank. If it stops then, you have a leaky solenoid valve on your RO delivery to that bay. Since it only does it occasionally you may have a leaking check valve at a bay manifold allowing water to back through the weep system and exit through a different bay. Check the suspect bay and make sure that it doesn't only leak when another bay is in use.
 
IB hit on it. IIRC you have Coleman self serve:

if you have medium pressure spot free you have Dema valves on your RO delivery system. If you have low pressure I think they use a GC 3/8" solenoid manifold. If you turn SFR on in bay one, and water starts coming out in bay two you have problems with bay two's solenoid. Look on your super saver pump panel by the RO panel, where your flowmeters are. i put a rebuild kit in one just yesterday on that wash I just bought. The pumping unit is about ten years old A rebuild kit is almost as much as a solenoid, It is a PITA but I will probably just put all new solenoids on there if I continue to have trouble, It stopped most, but not all of my drip.

The Dema by your pump is a medium pressure valve. It opens during MP presoak and/or wax if you have those options. It then allows the 'secondary regulator to function.It is usually set at about 400 psi. If you have problems with low pressure in a bay a stuck MP valve is one of there things you should rule out.
 
The problem is it only does it once in a blue moon. I have to wait till it happens again to try to track it down.
A few weeks back I had debris in 2 different tips in the same day. I had only had that happen once before in 7 years so I'm guessing that something blew through the lines. I was talking to Randy yesterday and we came to the conclusion that there maybe some debris getting caught in the solenoid valve. I need to just switch that valve as soon as it makes sense to shut down the bay. We have beautiful weather and are crazy busy.
 
I'm guessing it's the solenoid for the spot-free in that bay. If it's stuck open, whenever someone in any bay is using spot-free it will come out in that bay too. It should only require taking the top off the solenoid and checking it for debris - you'll want to turn off the spot-free pump. You want to do it as soon as you can, otherwise you'll end up with someone trying to use tire cleaner in that bay and getting only water.
 
It is the ro solenoid. If you turn on the ro in bay 2 it comes on in bay 1. I guess the valve I was thinking of is not the right one. Where do I look for the valve on a Jim Coleman pump bench?
Thanks
 
It's not on the pump bench. There's a separate bank of solenoids for the spot-free to the bays. If your had the spot-free pumped through the high-pressure pump it wouldn't do what it's doing.
 
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