Last night my boyfriend was outside when the pool pump kicked on and he discovered that it sounded like it might be sucking in air, despite the water level being higher than the skimmer hole. I told him to manually shut down the pump (it was 1am) and we’d look at it in the morning.
So this morning we’re still trying to determine the cause of the air sounds coming from the pool. I cleaned the skimmer basket, cleaned the basket at the pump, unscrewed the release valve at the top of the pump and we turned on the pump. No go.
So we turn the pump off again, I decide since the water level is slightly low, that we should manually fill it before trying the pump again.
But in the meantime, I decided to poke around the other components of my pool system. I have three in ground lids near my pool:
[ul]
[li]Skimmer basket[/li][li]Leveler[/li][li]???[/li][/ul]
The ??? is near the deep end on the opposite side of the pool from skimmer basket lid.
I opened it up and below it I see a another lid with a small handle in the center and two latches to hold that lid in place. I slide the latches, lift the lid and… darkness. It looks a little icky in the water there so I didn’t wanna stick my hand too far down but I did manage to pull out a dryer sheet that had made its way into the water. :dubious:
I called my parents as their pool is quite similar to ours, but they do not have this extra lid with their pool. The biggest difference between their pool and ours is that we have an automatic pop up cleaner system… so I think this might be related to that.
We’re going to head down to the pool store today and get their take on it too, but I figured I’d ask the fine folks at the Dope as I’m quite certain we have a pool pro or two (or just someone who also has this extra lid) on board. 
Any ideas what this lid is/does?