Quote Originally Posted by MyBlueDog
**One note: When my skimmer level is nornal l(half way up with water), and the pump is set on main drain, the air coming into the pump seems to disappear.
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This makes no sense to me.

Why would a correct water level in the skimmer (or lack thereof) dictate me getting air in the pump when the valve is set on main drain???
Maybe there's something to your theory about somehow pulling the dissolved O2 from the water...

More likely, the skimmer and the main drain are connected before the Jandy valve. I'm NOT a pool plumbing expert, but I know that skimmers can be plumbed with two outlets; one goes directly to the pump and the other connected to the main drain plumbing. Maybe one the builders will weigh-in and explain the reasons for that. If yours is plumbed that way, and the water is not at the proper level in the skimmer, the system could be sucking air in through the skimmer and into the main drain piping on the main drain side of the Jandy valve. (There's a picture of what I'm inadequately trying to explain about half-way down on the right side of this page:http://www.howibuiltmyownpool.com/mo...bing-first-day.)

One other thought, try a small brick chisel or the like instead of a screwdriver; much harder steel.