Air in Pump- strange scenario


May 6, 2010
Anybody have any ideas about this situation:

First my setup:
I have a Jandy 1.5HP PlusHP pump which goes into a Jandy CV 460 FIlter, then a Jandy AETI 2000 Heat Pump, Then the aquapure.
Next it goes to my Paramount 6 port in floor cleaning system.
I have one skimmer return and one floor drain [and the mdx safety drain mounted on the side wall].
In this scenario the pump primes fine but takes a while to fill up the last little bit of the pump lid and get rid of all of the air.
There still remains either some small air bubbles or a large air bubble...maybe 3 to 4 inches long. No air is coming out of my returns.
My pump NEVER loses prime...I'm just a little compulsive on why there is any air in my system. I have a new oring on the lid and have leslies pool lube on the oring and a bit on the pump.

IF I flip a switch and activate my 2 shear descent water falls, thereby bypassing the infloor cleaning system, within minutes the bubbles in the pump go away and I am left with a perfectly clear view of my pump filter basket.

If I then change back to the infloor system, shutting off the waterfall...the bubbles eventually come back...but only after a while.

When I am operating the infloor system, the pressure gauge on my cartridge filter reads around 20psi. When I am operating the water fall, it reads around 14PSI.

The return path for the water is identical in both scenarios. 50/50 skimmer and main drain.

I'm puzzled.
Any ideas?
Thank you.


TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
Silver Spring, MD
Welcome to TFP!

That all sounds completely normal. In-floor cleaning systems run at comparatively high pressures, which means lower flow rates. While the lower pressure when the shear descents are on means higher flow rates. At higher flow rates the pump is able to clear out all of the air bubbles, while at lower flow rates it isn't. There will always be some air coming out of solution in the pump stainer basket because of the negative pressure on that side of the pump. That air slowly recreates the bubble when you go back to the in-floor system.