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terry robert
Well pump noise

When the pump motor kicks on at my well it makes a groaning
sound. Then as the tank fills and the motor gets ready to shut
off, the groan becomes a loud growl and you can hear it all
thru the house and it even causes vibration in the house.
Any ideas?

Re: Well pump noise

It depends on what type of well pump system you have installed as to what may be causing the problem. It could be as simple as a water logged tank to a valve issue. The vibration inside the home is likely caused by abrupt water pressure changes in your pipes, really loud in galvanized piping. Try to Google well water systems and read through some of the info you find. That will help you learn what type of system you have and what the technical discussions cover for your system. Hope this helps. :) Remember, the longer you wait to fix a well issue, the more expensive the repairs - i.e. damage to faucets, water heaters, etc.

Re: Well pump noise


Like alot of other problems presented on an internet forum, this one can be near impossible to diagnose without being there.

Couple possible causes that come to mind would be -

1- If the supply line entering the house from the well is situated such that it is rubs up against the foundation wall or against a wood structural member on its way into the house or to the pressure tank in the house....the normal noises from even a pump in good condition can radiate and amplify in a manner that causes noises similar to what you describe. This is so whether the supply pipe is galvy, black poly or even PVC. Sometimes the line can be manuvered a bit so it doesn't rub and the noise then disappears. Or...a piece of heavy foam or similar can be wedged between the supply line and wall to eliminate the problem.

2- Your pump's bearings may be on the way out....or the pump motor's bearings may be on the way out.

3- Your pump may be cavitating. IOW, it isn't getting enough water flow thru the pump and so the water that is in the pump begins to heat a bit, the air in the water separates as it churns around in the pump ...and then those air bubbles get slammed into the pump impellers. That will make a lot of noise. Frequently a growling sound. Sometimes like pebbles rattling around in a tin can.

Cavitation can be caused if the water level falls in the well and the pump cannot draw enough in a constant manner to supply its desires/needs. It can also happen if the screen on the pump is partially plugged. It can happen if the pump wasn't properly sized for the work it has to do on any given well. (How far the water has to be lifted) IOW, a pump or motor that is too small for the work-load can't move the water efficiently and fast enough to provide the pump with the flow rate it needs to prevent cavitation.

If you happen to have a pump that is really borderline for your well's static water depth (how far the water must be lifted) in combination with a 20-40 pressure switch and then were to replace that with a 40-60 switch...a problem with cavitation could develop because the pump is now both starting up against and working thru out the entire pumping cycle against a higher work-load than before.

(Any pump utilizing a pressure switch will have to work harder toward the end of the pumping cycle than at the beginning because it has to push harder against the increasing pressure in the tank. More work = more noise even if the pump is good/properly sized. See #1 above. )

4- Cavitation can occur if the supply pipe from the pump to the pressure tank is too small of a diameter. (choked flow rate again) Use the size recommended by the pump manufacturer.

5- If this is a 240V pump, it is possible to have it run and pump water... but not properly or efficiently ...if there is an electrical supply problem on one of the hot legs. The pump would then run slower than intended and cavitation could *possibly* occur also. It depends. This could be caused by a poor wire connection somewhere or by a pressure switch that has one pair of the contacts worn enough that they don't make firm contact anymore.

Re: Well pump noise

Ok, you guys seem to know your stuff. I am getting air in my water pipes. Would be my guess that my tank bladder has a whole and that the tank is becoming water logged.
That said, how do I know how large of a replacement tank to get?
On the show they replaced one with one twice the size of mine. Mine is only tiny and I would assume has no water storage area.
Original pump replaced 3 years ago after a lightening strike, but I don't know off hand what type of pump it is. I only know that it a very, very, deep well.:rolleyes:

Re: Well pump noise


I seriously doubt that your pressure tank is waterlogged. It is the abscence of air in a tank that constitutes a waterlogged tank (no air head left).

We'll get to your tank in aminute, but for now I'll mention what I *think* is the likely cause of the air in your lines - probably a perforation or crack in the supply line to the wellpump....somewhere above the static water level inside the well casing. I'll presume a submersible pump for now and go from there with an explanation.

If there is a tiny/small crack/perforation above the water level it will not drastically effect the wellpump's ability to deliver water in a reasonably efficient manner to the pressure tank. However, when the pump shuts off the water standing above that crack/perforation can/will drain out the crack and air will enter to replace that water. Next time the pump starts up, that air gets pushed/injected into the pressure tank and voilla....air in your plumbing lines. (This is particularly so if you have a bladder-style pressure tank because the air is now trapped in the bladder with the water. I suspect you do have a bladder-style tank judging from your indications of its physically small size) There are also other ways that air *can* get into the water in a pressure tank, but this is the most likely/most common these days.

As far as the size of your pressure tank goes - Basically speaking, the bigger the tank the better (provided your well's recovery rate can supply water fast enough to keep up with a call for lots of water at once. I'll presume so for the sake of giving a simple explanation concerning tank size).

The reason a bigger tank is usually better is because most pumps should ideally be allowed to run for a minute or more without shutting down....per pumping cycle. Reason being that this amount of time or longer allows the pump to run cooler than "short-cycling" it and because hypothetically...another one of the hardest things on a pump is starting it up and getting it to running speed. Bigger tanks mean longer pumping cycles and fewer starts to supply X amount of water usage.

Also, starting the pump up and getting to running speed eats more electricity per second than when it is up to running speed. So short-cycling cost you more from your wallet, too.

That being said, your tank may not actually be "too small"...depending upon how much water your household uses. IOW, it would harder on a pump with a smaller pressure tank if it was supplying the needs of say 4 people than supplying the needs of one or two. So....deciding whether it is "too small" would require more info and consideration including the costs of replacing with a larger tank. They don't give them away unfortunately. If you're filling a swimming pool with the well, then definitely get a bigger pressure tank. If it's just you there...eating, showering, doing laundry,etc.....maybe not so important or cost effective.

Another thing that can and will cause excessive short-cycling is if your pressure tank becomes waterlogged (no air-head left at all or even not enough air-head). Without the proper air-head in it...it is effectively a smaller tank. Consider that if there is NO air-head at all.....everytime you draw so much as a tablespoon of water...it will drop the pressure enough to cause the pressure switch to turn the pump on...and then the pump will run for exactly the length of time it takes to replace that tablespoon of water and then shut off. On, off, on, off, on, off ...for as long as you are drawing water. This is exceedingly hard on a pump and should not be allowed to continue. The tank must be recharged with the appropriate amount of air (for the size of the tank and the particular pressure switch range your are using)... or the pump will have a very short life expectancy under these conditions.

Without knowing more about what size your tank is ...or what the pumping rate of your wellpump is...etc...I'll suggest that if your pump runs for less than 35-40 seconds to refill the tank, it's time to investigate the state of the air-head in the pressure tank and if that is correct....might wanna think about getting a bigger tank one day. To check the run-time cycle of the pump....turn on faucet or similar somewhere close by so you can hear exactly when the pressure switch kicks in and/or the pump starts....with a watch in your hand. The instant the pump starts, close the faucet and time how long it takes before the pump shuts off.

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