Banging thumping noise from Well pump

[Rquang]

Hello All,

I recently moved into a new house that uses a well pump. Prior to this, I have always been on city water and never had to deal with well pumps of any sort. Recently, I’ve been noticing a loud banging noise from the well pump that causes a the pipes attach to it to rattle. It seems to happen when the pressure drops to 40 psi and the pump turns on? Despite my lack of experience with well pumps, I do think that if shouldn’t be rattling like that. Has anyone had similar issues to this or know what the problem could be? I am planning on calling a plumber to come check it out this week.

I have attached a photo of my pump and a short little clip.

 

[Reach4]

I think you have a submersible (down the well pump.

Two things:

1. make sure the air precharge is set to 2 psi below the cut-on pressure. Air precharge is measured and set while the water pressure is zero.
2. remove, or remove the innards of, that check valve. It is usually best to not have a topside check valve. I think that is where your bang is coming from. Check valve labeled with yellow A in two places.
   

 

[Sponsor]

 

[Skoronesa]

........... I’ve been noticing a loud banging noise from the well pump ...........

I agree with @Reach4 Your well tank needs air. You're hearing water hammer as the bladder in the tank completely empties and the water stops moving for a moment while the pump catches up.

How long does the pump run for? Should be at least 45 seconds with a proper air charge.

 

[Skoronesa]

I think you have a submersible (down the well pump.

Two things:

1. make sure the air precharge is set to 2 psi below the cut-on pressure. Air precharge is measured and set while the water pressure is zero.
2. remove, or remove the innards of, that check valve. It is usually best to not have a topside check valve. I think that is where your bang is coming from. Check valve labeled with yellow A in two places.View attachment 70757

We use check valves all the time, should be fine. I've probably seen thousands of them installed.

 

[LLigetfa]

remove, or remove the innards of, that check valve. It is usually best to not have a topside check valve. I think that is where your bang is coming from. Check valve labeled with yellow A in two places.

I agree. A check valve works until it doesn't. It might already be too late to remove it and all be well. My guess is the water hammer already did damage upstream and when you remove the check valve it will expose the fault upstream.

There is a sticky thread at the top of this forum that explains why multiple check valves are bad.

 

[Rquang]

I agree with @Reach4 Your well tank needs air. You're hearing water hammer as the bladder in the tank completely empties and the water stops moving for a moment while the pump catches up.

How long does the pump run for? Should be at least 45 seconds with a proper air charge.

Usually about a minute or less to get it up to 60 psi.

 

[Rquang]

I think you have a submersible (down the well pump.

Two things:

1. make sure the air precharge is set to 2 psi below the cut-on pressure. Air precharge is measured and set while the water pressure is zero.
2. remove, or remove the innards of, that check valve. It is usually best to not have a topside check valve. I think that is where your bang is coming from. Check valve labeled with yellow A in two places.View attachment 70757

I think I have a 40/60, so I would have to set it at 38/58? Sorry this is all too new for me. And would eliminating the check valve replace the issue? I’m going to have a plumber come by this week to look at the issue and hopefully get it fixed.

 

[Reach4]

I think I have a 40/60, so I would have to set it at 38/58?

Air precharge pressure would be 38 psi.

And would eliminating the check valve replace the issue?

Probably.

 

[LLigetfa]

And would eliminating the check valve replace the issue?

What does that mean, replace? It may "replace" one problem with another problem.

The water hammer is likely from either a hole in pipe or the lower check valve not holding. This causes the water column to fall, drawing a partial vacuum behind the topside check valve. When the pump starts, the water column rushes in like a freight train at full speed and slams into the topside check valve.

There is a slight chance that removing the topside check valve may restore proper operation of the bottom check valve if'n that is the only problem. The water hammer may have destroyed to lower check valve and possibly split the pipe. You won't know until after you remove the topside check valve.

 

[Skoronesa]

I think I have a 40/60, so I would have to set it at 38/58? Sorry this is all too new for me. And would eliminating the check valve replace the issue? I’m going to have a plumber come by this week to look at the issue and hopefully get it fixed.

Shut the power to the well and run all the water out. The air pressure on the top of the tank(the valve stem, like on a bike/car tire) Should be just below the pressure that the well switch turns the pump on at. So if the switch kicks on at 40 than the air should be at 38/39. Should be fine as long as it's at least like 34psi. Having a lower air pressure will just shorten how long the pump runs.

I think your air charge is fine if it's running for a minute to refill the tank. I think the issue is the control box/capacitor inside. The pump's not picking up the slack soon enough.

 

[Valveman]

That extra (unneeded) check valve is causing the water hammer on pump start. Like LL says removing or gutting the check valve will solve the water hammer issue, but may let you see there is a problem with the bottom check, that will then need to be replaced.

Might as well start educating yourself on what causes these problems. Cycling the pump on and off, asd it is doing every 60 seconds or so, is what causes most failure in all the ater system components. Stop the cycling and all your problems go away. BTW, a CSV1! would go right in the same place as that unneeded check valve, Remove the check, install a CSV1A.

 

[Sarg]

When My second check valve was replaced .........

 

[Skoronesa]

When My second check valve was replaced .........

Why did you install a prv? Tell me it doesn't function like a normal prv, because otherwise you could dead head the pump if the pressure switch sticks on.

 

[Skoronesa]

I watched the video on the "Cycle Stop valve", definitely seems to act like a prv. My guess is they have some sort of high pressure bypass so the relief valve will still blow off if the pump stays on.

Never installed, worked on, or even seen one of those in person. This is the first I'm hearing of it. I don't know how much credibility to put in their claims of reducing cycles, but I guess it's just one of the many ways to skin a cat. Well pumps(good ones) usually last 20-30 years around here. Maybe we just have great water. If it's a submersible around here it almost certainly has a check on the tank tee and an appropriately sized well tank.

 

[Valveman]

Having been in the well drilling and pump business for more than 50 years, it blows my mind how many ways there are to skin that cat. I am even more blown away by how many people keep skinning it the wrong way. A good well pump can last 20-30 years or even longer, as long as it doesn't cycle on and off too much. But for people with irrigation, drip systems, heat pumps, or just a house full of kids, the pump cycles on and off too much and pumps don't last nearly as long. The average life of all submersibles is 7 years. They build just enough quality in pumps to make them survive about 7 years of average cycling. If you have more than average cycling, the pump may only last a short time. If you have less than average cycling, the pump can last even longer.

To be such a simple valve the CSV has a complicated explanation. The CSV has been on the market for a little less than 30 years, and it is still a closely guarded secret that pump manufacturers don't want you to know about. Goulds and several other pump companies blacklisted the CSV in 1994 as a disruptive product. They said, "The CSV makes pumps last longer and use smaller tanks. This company makes pumps and tanks. So, anyone who mentions a CSV will be fired immediately".

Yes the CSV kind of works like a PRV. But the CSV can never deadhead a pump and won't cause or let a pressure relief valve pop off. Eliminating or reducing the pump cycling will make any pump last longer. If you are getting 20-30 years now, adding a CSV could double that amount. There are also many other benefits for using a CSV. The CSV also eliminates water hammer and surging the well.

Of course having more than 1 check valve can cause water hammer that even a CSV can't stop. This is why the un-needed and troublesome extra check valve at the tank needs to be replaced with a CSV1A. Everything in a pump system is destroyed by the pump cycling on and off. When your system is set up correctly and using a CSV, you will have strong constant 50 PSI pressure in the shower as compared to the continually varying and dismel pressure changing from 40 to 60 over and over as happens with the old pressure tank method.

As for credibility of the CSV? How about a money back guarantee, a million happy customers, and a thousand or so 5 star reviews from as far back as 1993? Here you go.
https://cyclestopvalves.com/pages/reviews

 

[Skoronesa]

Having been in the well drilling and pump business for more than 50 years, it blows my mind how many ways there are to skin that cat.

I am really interested in this csv, going to look more into it.

I have a thread on the plumbing zone about interesting well systems. Where I live the well systems run the gamut. Many of the guys on the pz hadn't heard of most of the setups I posted. I would post a link but I am not sure that's allowed because it's another "competing" forum.

 

[Reach4]

Ever use a pitless adapter for submersible pumps? Beyond the freeze protection you don't need, it seems like it would still be easier in warm areas in some ways. It lets you sanitize your well and recirculate more easily. It could be compared to having a plug and jack vs hard wire electrical.

 

[Valveman]

I am really interested in this csv, going to look more into it.

I have a thread on the plumbing zone about interesting well systems. Where I live the well systems run the gamut. Many of the guys on the pz hadn't heard of most of the setups I posted. I would post a link but I am not sure that's allowed because it's another "competing" forum.

I never see much happening at pz. Can't find the thread you are talking about? Sure post the link so I can find it.
Thanks
Cary

 

[Sarg]

I frequented the PZ site for a couple days and learned quickly it was "Pros Only". The bona fide members treated outsiders like crap. Deleted that bookmark quickly.

 

[Valveman]

I frequented the PZ site for a couple days and learned quickly it was "Pros Only". The bona fide members treated outsiders like crap. Deleted that bookmark quickly.

Agreed! Not a homeowner friendly place. But I still keep an eye on them or they get to talking about things they think they know and don't really understand at all.