Big air leak

[ethany]

I am losing prime, can't find a leak. When I shut the pump off the cover for the skimmer by the pool blew off. Blew basket out too. Lots of air bubbles in the pump basket.

It will hold prime for awhile then lose it. There is a crack in the union,part that screws on to the threads. Water isn't leaking if there is its very minimal.

 

[Bama Rambler]

A crack that won't leak water will leak a lot of air. Also sometimes pressure will seal a leak but under a vacuum it will will leak.

 

[ethany]

Why does the skimmer lid blow of like an explosion?

 

[Bama Rambler]

When you have an air leak it pressurizes the filter with air. When you shut the pump down the air rushes backward out of the filter, pressurizing the system, and since the skimmer is where it escapes, it blows out there launching the skimmer lid. If you were to purge the air out of the filter just before you shut the pump off it wouldn't do it.