My Pentair VS pump keeps getting air bubbles(not enough to activate the auto prime).
I have the timer set to circulate two hours twice a day at 1500 rpm. This seems to be enough to keep the sides from getting slimy and keeps the water crystal clear and 92 degrees.
The bubbles seem to develop when the pump is off and stay there at 1500. If I raise it to 2300 the air disappears and stays that way until the next timed cycle.
I tried a new o-ring and tightening all the unions on suction. I cracked the vent on the filter and heater plate on the pressure side to check for air trapped in high spots. All joints are visible including the jets and skimmer.
Everything is above the water level in the pool, and I do here water dripping back in the heater plate, that is the highest point in the system, when the pump shuts off.
Could it be air trapped on the pressure side that creeps down the pump outlet? Any thoughts?