Check valve location

It always matters. Check valves in industrial installs are usually placed downstream of the pump, because of restrictions to flow through them is less noticeable to the discharge.

Does it really matter? As far as I know, it makes no difference, well, if, of course, everything is done correctly

Thank you Old Biscuit, you nailed it. The pump was new last season. Problem is with pump check valve. Install on the tank side is the best solution. Thanks to all.

troubledwaters wrote:
I would put it on the intake side of the pump, so the pump stays full of water. YOMV

Exactly ^^^^^

IF pump internal check valve is leaking and you put a check vlave in-line on discahrge side of pump the pump casing will depressurize and pressure switch will close causing pump to short cycle.

If you put that check valve in-line on pump suction side then pump casing stays pressurized and pump will only start when SYSTEM pressure drops from opening a faucet etc (OR leak in system)

OR
FIX pump internal chekc valve

I would put it on the intake side of the pump, so the pump stays full of water. YOMV

Put it on the spigot and you're good to go....Dennis

I don't think it would matter, but I would put it after the pump if I used a separate valve. I would probably consider replacing the pump, and just go with pump installed valve.

Jerry