Newbie pump/sand filter AIR question

Hello All.
I opened my first pool last week, moved in to a new house that has a 24' AG with Hayward sand filter (model s166T) and Hayward Power-Flo XL pump. I seem to have some air in the system, as the return is flowing strong, but bubbling some in the pool. There's a vortex of air and water above the strainer basket in the pump, and the skimmer seems to be slurping water at 3-4 second intervals. If I shut off the pump, there will be 3-4" of air in the pump strainer visible thru the clear top. I've had some luck bleeding this air out by slowly opening the top a 1/4 turn (w/the pump off) until water squirts all over my feet. Occasionally the pump will reboot and there will be no visible air (and the whole system will run much quieter, ie: no slurping), but sometimes I restart the pump and it sucks all the water from the strainer, as well as some air as it gurgles, and the pump is filled with air and water again in the basket. I've read a bit about releasing air from the filter, but I can't seem to find a release on my filter, and the user manual I d/l from Hayward makes no mention of one either. Thx.

There is no air bleed on that filter. It's a smaller version of my S-244T. If you look at the manual, the center pipe from the laterals is a loose fit to the valve assembly and that's where any trapped air would escape. Sounds like you may just have a low water level and are sucking air from the skimmer on a cyclic basis. For now I'd just try raising the water level an inch or so and see if the situation changes. With good flow the trapped air in the pump strainer basket should purge itself.
Al

I know when I get that 'vortex' in my skimmer when starting up it means my debris basket in my pump needs to be cleaned.