I have a WhisperFlo. For other readers, this unit has a clear plastic lid
so you can see any cavitation.
A 1 inch inlet might be insufficient.
What hp is this pump? What was the original hp?
If you are now running too much pump, a solution might be to install a ball
valve on the outlet and dial it down a bit.


"Lee" wrote in message
...
I realize this is not directly related to the purpose of this group,
so if you know of a better place for me to ask, please let me know.

We have a problem with our Pentair-WhisperFlo pool pump. It is not
able to fully prime, even with addition of water into the pump body
directly (via the volute/strainer basket). It seems able to draw
about 1/2 the amount it needs to fully prime and operate. We have
replaced the pump impeller, and have tried to clear the inlet line (1
inch PVC pipe) through pressure from a garden-hose expansion nozzle
from both directions. Nothing has worked. We believe there is
probably a blockage/obstruction of some kind in the pipe between the
pool and the pump (perhaps a tree root that has gradually penetrated
the pipe).

Does anyone have any ideas of what else we can do to find out if there
is an obstruction in this inlet pipe? Our resources are quite tight,
so hiring a plumber to come in with specialized/optical equipment
would be beyond our reach at this point.

Thanks for any suggestions you may have.

Lee