What PSI should be in my well expansion tank?

[CobyRupert]

2 lbs under the lower setting on your pressure switch. So if the switch is a 30/50, tank should be set at 28 lbs.

Keep in mind you need to shut the water off and drain the water out of the tank and bring water pressure to 0 before checking the pressure of the tank AND a short cycling pump (pump on , pump off, pump on pump off causing pulsation ) is usually a water logged tank (old style), loss of charge through schrader valve or bad bladder in the tank, NOT a bad pressure switch. Seeing you had a pressure reading of 45 I am guessing you did not drain the tank...............

I think they are saying: Note the water pressure when switch normally turns pump on. Then turn off pump, open a faucet until water pressure is zero, then check that ballast tank’s air bladder pressure is 2 psi below the pressure that the switch turned on at, that you first noted.
You definitely need a gauge somewhere in your system.

 

[Oldoak]

My thoughts exactly. Need to drain the tank, then check pressure.

Hopefully you fixed the issue. Pulsating pressure could be a number of things. But it is something that shouldn稚 be ignored. If it is a bad pressure tank, which causes the short cycling, that is hard on the pump.

Among other causes of short cycling is a leak in the well pump piping in the well. Had that problem develop just this last October.

We had to replace the well pipe which was installed when our well was drilled 45 years ago. The deep well submersible pump was still going strong after all those years but we replaced it with a new one as long as the pipe had to be pulled.

 

[gary49]

Yes, very likely bad pressure tank. They're usually blue, and stand upright. Short cycling /pulsation is caused by failure of the bladder in the tank. Tank is mostly air in the bladder/ water under the bladder if it hasn't failed. Reason for air is that water is incompressible. Turn off electricity to pump, run water at a faucet until it stops, and then put your hand on the top of the tank and give it a shake, should be light as a feather, since it should have no water in it. If it heavy and/or you hear water sloshing, the tank is done. Get a new one installed, I usually replace the tank tee, gauge and pressure switch with the new tank, tank air precharge should be 2 psi below cut in setting of the switch. Reason for the 2 psi undercharge is there needs to be a little water in the tank when the switch cuts in, otherwise you get an interruption of the water flow every time the pump cycles on. Tank will come with precharge in it, may have to let air out if new switch is 30/50.

 

[Egon]

Put on a new pressure gauge & check the pressures at which the pump comes on and shuts down.

 

[Langanobob]

Pump controls are pretty simple but I suggest calling a well/pump service company to come out and check and adjust your settings. They can walk you through everything and by the time they’re done you’ll be a relative expert. I think they will come out for relatively cheap and I’ve even got flyers in the mail offering free “ tune ups” in the hope that you’ll call them when you need a new pump or other $$ work done.

Rapid cycling like you described is a serious problem and kills pump motors in a short time and as mentioned earlier you may have a pressure tank failure.

 

[Ford850]

Put on a new pressure gauge & check the pressures at which the pump comes on and shuts down.

This is the proper first step. Do this, then drain and add/remove air from the expansion tank to be 2 psi below the point that the new gauge says the pump comes on. You can't just go by what the switch was originally set at since it might be different that original. Then monitor for issues after some more use.

 

[plowhog]

Thanks for the responses.

So it seems I first need to open a faucet and watch the "cut-in" and "cut-out" pressures when the pump cycles on and off. That was I know the cut-in pressure, regardless of what is printed on the cover of the switch (in case it was previously adjusted.)

Then drain the entire system, and test the psi in the tank. If it is anything different than 2psi below the cut-in pressure, adjust it to be 2 psi below cut-in pressure. Then wait 15 minutes, and re-test the pressure to see if any leaked down?

 

[Ford850]

It might leak down over days or weeks too. There are a various levels of quality in these bladder tanks, and many of the lower cost tanks have bladders that develop slow leaks (pin holes) as they deteriorate. I was surprised to read about many failures in less than 5 years. My last tank lasted 12 I think, and that was a higher quality tank.
A slow leak can give you time to decide when and what you want for a replacement.

 

[Oaktree]

There are a various levels of quality in these bladder tanks, and many of the lower cost tanks have bladders that develop slow leaks (pin holes) as they deteriorate. I was surprised to read about many failures in less than 5 years. My last tank lasted 12 I think, and that was a higher quality tank.

Guess they don't make 'em like they used to. Haven't had to deal with pumps in the last almost 15 years since we get enough pressure from gravity alone here (well is on a hill behind the house, probably 20-25 feet higher), but the tank & bladder were still good at my previous place when I sold it in '06. I'd installed the pump and tank new in the late 70s. I wanna say it was from Sears.
Only thing I ever replaced was the pressure switch. Thought I'd be clever and replace the original 20/40 with a 30/50 to get a little more pressure, but the pump couldn't do much more than 40 psi. Definitely not city water pressure, but adequate.
Both places had shallow wells, not artesians.

 

[Clint S]

Thanks for the responses.

So it seems I first need to open a faucet and watch the "cut-in" and "cut-out" pressures when the pump cycles on and off. That was I know the cut-in pressure, regardless of what is printed on the cover of the switch (in case it was previously adjusted.)

Then drain the entire system, and test the psi in the tank. If it is anything different than 2psi below the cut-in pressure, adjust it to be 2 psi below cut-in pressure. Then wait 15 minutes, and re-test the pressure to see if any leaked down?

About right. Keep in mind that your tank is probably overfilled now. I would also check for leaks by your gauge after you install it. Check pressure do not use water for an hour and recheck. If you do nt have air in your water probably don't have a leak from tank to well (if there is a check valve ) Also keep an ear out for pump coming on when no water is used. (middle of the night)