Do any of you "pro's" know what causes a checkvalve to make a 'thump-wham' sound when the pump comes on.
This is a check valve located near the pressure tank that is supplied by a sub pump in a deep well.
It's a 1" brass check valve, it operates quietly for a few months ,but eventually upon activation it has a quick 'thump/wham' sound upon opening.
This makes the whole supply line move slightly for a second. It does open and the system is operating fine. It's just this noise that it makes has me concerned as to any damage it may cause.
I have replaced this valve 3 times in the last 3 years. When a new one is installed it works smoothly for a few months and then starts to make this thump/wham.
What can cause this, and are there any "silent type of check valves that will not stick?
My theory is that the water from the Well, being slightly hard, causes a chemical reaction to the valve's seat (poppet)and so to speak creates a "weld" or sticking effect, and temporarily delays the opening of the valve.
What do you think?
Thanks for any reply