I ordered a Jabsco 2.9 par-max 12V 40psi fresh water pump and have been sent the 50psi version in error. The difference is the 40 psi one is rated from 15 to 40 psi and the 50psi one is rated from 20 to 50 psi. Could I get away with the one I have been sent?
There's an adjustment screw on the bottom of the pressure switch that will let you reduce the pressure a bit. But be careful! Too much pressure can lead to leaks and even permanent damage of plastic fittings in the system. Better to get the right pump.
Thanks for the info. I have decided to send it back and get the replacement rather than messing about.
Neil