I have a 15″ dia diaghragm tank holding water pumped from a point. I have more than one problem. First problem is that the pressure drops to zero for a few seconds before the pump comes on. Shut off pressure is about 50. No amount of fiddling with the pressure switch will fix this – I’m assuming the diaghragm for the pressure switch is no longer operating properly – dirt, etc. Easy enough to replace.
The bigger problem is that after the pump shuts off, the water pressure starts dropping, even with no water running anywhere in the house. So of course the pump is coming on ever 10 minutes or so. I’ve emptied the tank, and it has the proper air pressure. If the diaghragm were ruptured, I wouldn’t expect to see this – no? Could the water be backfeeding through the pump back into the well? How do I figure out what’s happening?
Replies
Sounds like a defective check valve. Your well is losing its prime as the water flows backwards into the ground. That's why your guage reads zero. Time for a new valve.
I think you're right. This would also explain why, when the motor starts up, the pressure remains at zero for a few seconds, then jumps to 30. That's when the water hits - the sound changes - ding ding aha.
I think if the pressure valve was working properly, the thing would be cycling even faster than it is now. Maybe it did that for a while and just finally wore out. I dunno.
BTW, I must say I only recently bought this house. Just wanted to pre-empt any stupid homeowner comments... ;)
Where is the checkvalve? What does it look like? Anything to know about getting a new one? I suppose I can probably answer these questions with a bit of googling, but I'll accept enlightenment from anywhere I can get it.
Everything's all fixed now. I had two problems.
First was that there were two pinhole leaks directly above the footing valve. I couldn't find the checkvalve to save my life, so I asked my neighbor. He knows my house better than me. So I pulled the pipe up, and replaced it. The valve was fine.
Then I put on a $30 new 30-50 pressure switch. Turn on the power, and the pressure runs up to 65 before I shut it off. So I pulled off the tube connecting the switch to the impeller housing. It is plugged, and so is the hole into the impeller. Clean them both out, and what-da-ya-know, everything works as advertised. Blew $30, oh well.
Beer and burger time.