So I was cutting the grass around my pool on Sat July 4th and noticed lots of big air bubbles coming out from one of my returns and then noticed the actual return eye sitting at the botom of the pool...not good. I went over to the pump saw it was half full of water. I turned off pump checked all the skimmer baskets, looked for leaks etc.. I found nothing. So then I thought maybe I need to backwash, so I did that. Also from reading this site I thought maybe I needed to relube everything, so I did that.
The water level was a little low and I thoguht maybe the skimmer were sucking in air so I actually empitied the attached spa into the pool and raised the water level and refileld the spa with a hose.
Turned everything back on and seemed normal...back to cutting grass.
Finished cutting, now weed wacking,and of course I walk past the pool, large air bubbles, return eye in the bottom of the pool. I have never had a problem with air in lines so I am freaking out at this point. I walk around again and check the skimmer baskets. Only this time I get down on my hands and knees and look closer at the skimmers, I put my hand in the water on the first one and felt the weir door and low and behold..there is a large rocket firework jammed into the door and keeping it from opening. Could not see it at all from walking around the pool.
Looks like with the weir door not opening that the skimmer would work OK at low speeds and even though not a lot of water was getting into the skimmer it was not draining completely. But at higher pump speeds it would suck more water than was being let in by the stuck weir door and it would start sucking air creatimg a large air pocket that would blow out the first return in the pool causing the eye to blow out.
Thankfully it is fixed, but just a lesson for the group!, stuck weir doors are no good!! (dang nieghborhood kids and their ireworks!!!..ha!)