Please help me to diagnose a circulation problem

[milamber26]

Please help me to diagnose my water circulation issue. I have a 1 hp single speed pump that goes through a 38 sf Anthony Apollo DE Grid Filter. Up until now the whole system was pumping fine with good suction at the skimmer and a good flow at the returns. Yesterday I backwashed the filter prior to adding CYA to the pool and when I was finished the pressure was 12 psi at the filter (which is normal after backwashing). I ran the pump all last night and all day today to let the CYA dissolve and when I checked the pool after work today at 5:30 PM, the system seemed to be running fine and the pressure at the filter was 10 psi. At 6:00 PM, the system shut off automatically as it was programmed to do. I turned the pump on manually to allow more time for the CYA to dissolve and the pressure at the filter was 0 psi. You could hear water moving through the pipes, but it was moving significantly slower than normal. The flow at the returns was approximately ¼ as strong as normal. Is this a pump issue, or is there a blockage in one of the lines?

 

[JohnT]

It sounds like you have an air leak that isn't letting your pump fully prime. Check the strainer basket lid gasket and your skimmer weir for free motion. Check that the water level is up far enough in the skimmer to avoid a vortex in the skimmer. Finally make sure all the valves for the skimmer and drain are open.

 

[milamber26]

John,

Besides the things that you said, how would you troubleshoot an air leak in the suction line?

Thanks,
Scott

 

[duraleigh]

Milamber,

Is there visible water in your pump basket strainer? Is it partially filled with air or just water?

 

[milamber26]

Duraleigh,

It's filled with water. Is it possible that the problem could be caused by a blockage because of too much DE in the lines? I recently backwashed and am not sure if I added too much.