Pump valve ????

[pokerfish]

Is it better to put a valve on the intake of a submersible pump or the outtake of the pump? Why? Thank!!!

 

[millerkid519]

Valve on outflow. If you put the valve on the intake of the pump it will starve the impeller housing and harm the pump

 

[duanes]

Always on the outflow.
Centrifulgal pumps are designed for outflow throttling.
If you put in on the inflow, you are pretty much assured the pump will quickly burn out if choked.