Air in lines after well pump motor replacement

[Darlyj]

Hi! I'm hoping someone here will have a little insight into what is going on. We have a shallow well that is (I'm guessing) thirty feet or so from the well pump. The pump is directly under my daughter's room.

On Sunday, I noticed that our water pressure in the house was not recovering like it normally does. The pump was short-cycling when building pressure, but would eventually get there. My husband and son replaced the pressure switch to no avail. We called a local plumbing guy, and he made sure the switch and tank pressure were set properly, but diagnosed the issue as the thermal switch in the pump motor. When he left, everything at that point was working as it always had minus the short-cycling. We called a well company, and because we have a Gould's pump, he suggested that we replace the motor as they are apparently really good pumps. They did that yesterday. Because of the set up, they had to pull our (too small) pressure tank that sits just above the pump. I had noticed it sucking a little air after they left, but it REALLY started sucking air when my son was in the shower last night. Also, I had one heck of a time getting cold water through the faucet. I checked, and they had not tightened the pressure tank connection enough so it was leaking. They sent a different guy out to fix that today, and while the leak is gone, I'm still getting significant air in my lines after the pump kicks in. It takes much longer for the pump to get the system to pressure as well. I've crawled under the house and checked every line with everything at normal pressure. There are a couple of very slow drips where an old lines were closed off, but nothing that should cause a significant amount of air to be drawn into the lines. And it holds pressure like a champ.

We have been in this house almost nine years, and the only time we have ever had a problem with water pressure or air in the lines was when a line split last year, which was fixed asap. Outside of that, until everything was put back together yesterday, it's literally never been a problem. The guy today did say that because of how everything is laid out, they had a heck of a time trying to prime the pump.

Any ideas? I sincerely appreciate any suggestions.

 

[Reach4]

Could be a vacuum leak.
Cover accessible joints on the suction pipe with shaving foam, and turn on the pump. If you are covering the leak, the shaving foam should suck in.

Don't forget the connection right at the pump.

A leak in the path to the pressure tank should spew water rather than pass air.

 

[Sponsor]

 

[Darlyj]

Could be a vacuum leak.
Cover accessible joints on the suction pipe with shaving foam, and turn on the pump. If you are covering the leak, the shaving foam should suck in.

Don't forget the connection right at the pump.

A leak in the path to the pressure tank should spew water rather than pass air.

Awesome. Thank you for the suggestion!

 

[Valveman]

The pump was short-cycling when building pressure, but would eventually get there. My husband and son replaced the pressure switch to no avail. We called a local plumbing guy, and he made sure the switch and tank pressure were set properly, but diagnosed the issue as the thermal switch in the pump motor.

This sounds like the cycling was caused by the thermal overload. It just kept resetting itself until the pump got up to the cut off pressure. Having "too small a tank" without a Cycle Stop Valve will cause too much cycling. Cycling too much like that will cause the diaphragm in the tank to break, waterlogging the tank, and causing real "rapid cycling". The thermal overload starts tripping regularly, and lets the pump "cycle" up to cut off pressure eventually. These thermal overloads are auto-resetting, so you don't know how bad the cycling problem is until you need new pump, tank, switch, and everything. Planned that way.

None of that should have anything to do with air in the lines. Either the pump is sucking air or there is a leak in the suction line as was suggested. Having a check valve at the tank can make the air problem even worse.

 

[2stupid2fixit]

If you have a an ordinary pitless connection no matter which manufacturer made it, your pitless gasket could be leaking, they dont last forever. that will cause air, and short cycles, and will tire out an older pump motor to thermally protect itself. If you have a pitless setup, it's a great source for air introduction into your system if the gasket has deteriorated. To my knowledge, the gaskets on pitless connectors are made of materials like nylon, rubber, neoporene and leather. The leather ones supposedly last the longest because they are made of animal material, the others I mentioned can go anywhere from a year to 30 years but since they are some sort of polymer they are subject to electrochemical degradation. To valveman's point, if you have check valves after the pump itself, they will exacerbate the issue.

Forget about all the tech mumbo jumbo. Do you have a pitless connector? If yes, Are you sure it is not the source of air sucking?
Sometimes "reputable" well companies will sell you a new pump when a failed $10 gasket is to blame. Out of the goodness of their hearts, they replace your pitless gasket and dress it up nicely for free, since they did install that expensive new pump for you.

 

[Valveman]

With a check valve at the tank a leaking pitless can introduce air into the system, but it still only cycles when you use water. Without a check valve at the tank a leaking pitless cannot introduce air into the system, but it will cycle on and off when no water is being used.