Would this be caused by water hammer and is it from the check valve.

[jet18357]

After replacing my pressure tank and all associated hardware I've noticed a serious water hammer issue when the pump kicks on. It's a 30/50 switch, no low pressure cutoff, verified tank set to 28 or so with a new tire gauge and empty tank. When the pump kicks on the gauge drops to around 15 or so but immediately jumps back to 30 and then builds it also causes a bucking in the pipes directly after the T. Could this be caused by the check valve? I only installed one because that's how it was previously, I didn't notice this issue before but the tank was bad. Thanks for all you help.

 

[Reach4]

Submersible, or above-ground pump?

If above-ground jet pump with one pipe to the well, you probably have to reduce the air precharge in the pressure tank. Air precharge might need to be 25 or 26 PSI. You may need the check valve -- depends if you have a foot valve..

 

[Sponsor]

 

[jet18357]

Submersible, or above-ground pump?

If above-ground jet pump with one pipe to the well, you probably have to reduce the air precharge in the pressure tank. Air precharge might need to be 25 or 26 PSI. You may need the check valve -- depends if you have a foot valve..

Submersible pump. I at first thought maybe when I changed the pressure switch I had set the tank to low and that was causing the drop and water hammer but like I said it's at right around 28.

 

[Reach4]

With the pump not running, compare the air pressure and water pressure. They should be about the same. The point is to compare calibration of the air and water pressure gauges.

With a submersible, we expect there to be a working check valve down at the pump. It would be best to remove or gut the topside check valve, especially because you get that starting bang.

 

[Valveman]

Water hammer on pump start is caused by having more than one check valve in the system. One check valve on the pump is the only one needed. Cycling on and off is what caused the tank to go bad and will also destroy the pump, check valves, pressure switch, and everything else in the system. Adding a Cycle Stop Valve will solve all those problems and make the pump, tank, and everything else last longer while supplying strong constant pressure to the house.

 

[Sarg]

I suspect it was common practice for installers to include the above ground check valve to maintain pressure within the well tank which actually hides any issues within the well such as a bad check valve at the pump or leaking pipes.
I replaced mine with a CSV per Valveman's guidance ... No regrets.