Air in Returns and Filter

[BluenShiny]

This topic was split from This thread for better response. Bama

I'm curious what was found here? I am trying to figure out a problem that is very similar with a Dynamo Pool Pump. The basket is full of water when running, yet air is returning to the pool. The air is also constant from the air relief valve in the filter. I only notice air coming into the basket when the pump shuts off, and it almost appears to be coming in from the discharge port inside the pot. I'm about ready to rebuild the pump with a new gasket, impeller and everything, but I'm not sure if there's any freak cases where cavitation will cause bubbles to make it all the way out to the returns.

 

[Bama Rambler]

What you have is a suction side leak. The Dynamo pumps have a threaded connection between the pump casing and the basket.

Given your description of the air in the return but not in the basket until you stop the pump, I bet that the o-ring between the pump basket and the casing is leaking. That would be the first place I checked.

 

[duraleigh]

There is an article in Pool School on finding and fixing a suction side leak.