I live in NY. Ground is frozen. Just diagnosed that I have leak in my water line or well pump between the house and the well. It's a submersible well brand new 55 feet in well and 60 feet from house. I was getting hammering in line and shaking. I just cut line in basement and installed a check valve, and no more hammering or shaking. And holds good pressure now. But I have very low pressure in cottage now. Any ideas why? Only other thing I added was a union between the brass t and pressure tank for easy connect.

Just to be sure (after reading your previous posts under a different thread), you did install the CV between the pump and tank, and not between the tank and the house? As I understood, this was going to be a temporary measure to overcome a leaking pipe until the ground thawed.

When you say you have low pressure in the cottage, do you mean from faucets? If so, have you cleaned the aerators?

Thanks for responding. Yes the CV is in the basement as it enters the wall but is about 4-5 feet from the pressure tank. I almost have normal pressure in the shower now. But just drips in the kitchen sink small trickle hot and cold, but if I use the spray nozzle there is OK pressure in that. The hot water in the shower is almost normal, and the cold only about half pressure of what the hot is.

And yes. I took the aerator off and same water pressure without it on there. Its only 2 weeks old.

What kind of piping do you have where you installed the check valve?

Black 3/4" poly

Is it possible that you got some bits of piping in the line as you cut the line to installed the check valve?

Water pressure will be the same hot and cold at all faucets. Only logical explanation is that there is some debris in either the stop valves or the faucet. Debris would move to the first faucets used. Since hot and cold are blocked most likely faucet. Remove kitchen stems, hot and cold if two handle, remove cartridge or ball is single handle. Inspect and clean. Briefly turn on water to flush pipes.

I almost have normal pressure in the shower now. But just drips in the kitchen sink small trickle hot and cold, but if I use the spray nozzle there is OK pressure in that. The hot water in the shower is almost normal, and the cold only about half pressure of what the hot is.

Sure seems to back up HK's theory.

I removed lines from kitchen sink and put the ends in a gallon jug and I have tons of water and pressure when I turn on the ball valve. So I have debree in the faucet somewhere. Thanks all.