Air in Well Water System?

[Keith Stelter]

I got a new well put in about 3 years ago . It's down about 80 feet, and the guy who put it in said that the water level was at about 65 feet at the time (giving me 15 feet of water in the well). It has a submersible pump and I have an 80 gallon bladder tank that I put in last year. Recently when the pump kicks on there is air in the pipe that gets pushed up into the system before the water starts pumping in. You can hear it for about 10 seconds, and when you turn on faucets you get a blast of air before the water comes out. As soon as the air purges out there is no problem until the pump runs again. If I open several faucets to keep the pump running it will run water with no air in it at all. I know that the only check valve in the system is built into the pump at the bottom of the well, and I'm wondering if that check valve failing could cause this problem. The bladder tank pre-charge is set at 40 PSI, and the pump is set to turn on at 45 and off at 60 PSI. I don't know if a hole in the bladder would cause this situation or not? I drained the whole system down and the bladder tank still measured 40 PSI with the pump off and the pressure all drained from the system. Any advice would be greatly appreciated!

[Vic Dura]

On Sun, 5 Aug 2007 13:19:56 -0400, "Keith Stelter" wrote Re Air in Well Water System?:

My guesses would be:

1) faulty check valve

and/or

2) leak in piping system that allows air to enter the pipes as water flows back through the check valve

[rabbid]

faulty foot valve or leak

[dpb]

...

Or a combination most likely given the symptoms, I think.

The foot valve leaking would allow the water column to go down between pump periods and that would cause a partial vacuum as the column drops. Any pinhole in the standing pipe above the water table would suck the air in even if too small to be observable in output performance yet.

Air leak in the tank would end up w/ "waterlogging" the pressure tank w/ the subsequent characteristic short-cycling. If that's not happening as it sounds as if it isn't, then the air ingress has to be elsewhere.

Can't be on the inlet side of the pump or it wouldn't go away when running. Can't be in above ground visible pipe or there would be a visible leak when well is running (even if small). Could, I suppose, be in buried pipe section but the standing pipe in the well is most probably imo.

--

[M Q]

If there is truly only one check valve that is in the pump, then the entire system above the pump will always be under pressure, even if the check valve is leaky and any leaks, except to the bladder, will leak out water and not leak in air.

[Harry K]

Since it is impossible for air to be sucked into a pressurized system, the only way air could be sucked in is for the system to drain down to zero pressure first.

Failure of a footvalve (in the pump in this case) would result in the system draining to zero at each pump shut off and suck in air at that time or for the pump to repeatedly cycle keeping the pressure at or above cut-in and again no way for air to be "sucked in".

Well water commonly contains entrained air that will separate in the pressure tank. That would be my guess at his problem but it does seem a bit extreme.

Harry K

[Harry K]

Correction. There is a way for air to enter a pressurized system - a venturi but that would be extremely unlikely in a common water system.

Harry K

[jmagerl]

I can speak from experience having just spent $3000 to replace the pipe going to the house. The foot valve does not have to be bad in order to have air enter the system. The system from the pitless adaptor on down was pressurize and it held pressure very good. YEt we had air in the system. When well originally was installed, they used 80ft of galvanized pipe. THere was a leak at every joint caused from the removal of the galvanization during the threading operation. The plastic barb used to connect to the pitless adaptor was also cracked, The only clue I had about any of this was air in the pipe and short cycling on the pump. THere was no visible water at ground level but if you stuck in a 4 ft metal rod in the ground it was very easy to do and it came back muddy.

TRy the rod trick right at the well to see if the pitless adaptor is cracked and if you know where your pipe is, move along it at 5ft intervals to see if you can find a leak (turn the power off just incase you hit the power line),