Check Valve in Pump

[barngal]

When I purchased my PK125, I was advised that I needed a brass check valve in my submersible pump (or at the foot?)
I checked with my well company, and their records show that my check valve is in my pump, which is most likely a Jacuzzi pump paired with the Franklin motor.
Their records indicated that the only check valve down in the well is inside of the pump, that there was check valve above the pump/motor other than the one above ground (which I will leave out of the new install).

Assuming that is the case, that the check valve is inside the pump, is it safe to install the PK125? The last thing I want to do is have an expensive pump failure because of I installed my PK 125. My pump is 10 years old, and I want to keep it going as long as possible. If I risk damaging the pump, I'll just delay installation of the CSV system when the pump has to be replaced.

Please advise  Thanks

[Cary Austin]

Installing a CSV makes no difference about the check valve.  You still need one on the pump and no where else.  It is the pressure tank/pressure switch part of the system that requires a check valve, not the CSV, just as it has always been.