I would like to know "why set at 50psi" I set mine to 60 and pressure still climbs to 70? I am having a hard time figuring out the "why's" It does not make sense to me? Well pressure switch is set to 40-60psi. Check valve is in my iron filter head.
No big deal. It can climb to 100 and more without a problem for a dedicated thermal expansion tank.. You want it to not get close to the 150 where the pressure relief kicks in.
You get the maximum effect from the tank if you set it to the highest pressure for your water supply. So with 30/50, then 50 would be optimum. If 40/60 pressure switch setting, go 60.
If you have a softener, there is additional consideration.
1. You don't want hot water getting the softener hot. So having some length and volume of pipe between the softener and the WH can let the water cool before expanding into the softener.
2. Water expanding into the pressure tank due to thermal expansion will register as flow (phantom flow). I do that. Small amount of extra flow is recorded by the softener, if your calculations are that critical.
To avoid #1 and #2 totally, add a check valve at the output of the softener, and add a thermal expansion tank. I don't do that.
live where we are governed by UPC. I have a standard well system (not constant pressure) that operates between 30-50psi. The system is closed because there is a check valve where the water supply enters the house.
With a submersible pump, you don't normally want such an above-ground check valve. With a shallow well (suction) pump, you would like the check valve to be as close to the intake as practical. Ideally it would be down the well. A foot valve is a check valve and strainer combined.