air in return lines

[bkfamily1]

If everything is correct with my pool, should I ever have air in the filter basket on the pump inlet?

I have an in-ground pool. With the valves in the return lines to the skimmers and the main drain both fully open, there is no air. I have a "chugger" type pool cleaner. To get adequate suction to operate the chugger (measured with the regulator that comes with the cleaner to check suction), I have to close the valve on the main drain return line about halfway and plug the line in the bottom of one of the 2 skimmers. As soon as I close the main drain return line valve halfway, I start to see air bubbles coming out of the return line and into the pump basket. When I plug one of the skimmers, it gets worse. When I plug in the chugger, it gets really bad, and the pump starts to lose suction as it cavitates.

I checked to be sure the water level was not low allowing air to be drawn into the skimmers. And the seal on the pump basket lid is in good shape, clean and lubricated (plus the air appears to be coming into the basket from the return line when looking into the clear lid).

This pool was installed late last summer, and this did not happen then. It has been doing it all summer this year. The company that installed the pool have looked at it. They originally said something was wrong. But after searching for leaks, digging up and working on some of the lines and not stopping the air, they are now saying they do not think anything is wrong. They say it is leaks in the hoses for the chugger. But it does it when the chugger is not connected. It also does it when the chugger is plugged in even if I ensure the line and the chugger are completely submerged.

Any help would be greatly appreciated by this new pool owner!

Thanks

 

[jblizzle]

Welcome to TFP!!!

First, you are talking about suction lines (skimmer, cleaner, floor) and not return lines (to the eyeballs in the wall).
You are correct you should not see any air in the pump basket (with the exception of some stationary bubbles at the top if you are running on a lower speed).

As you are closing down suction lines, you are increasing the suction through the other paths and thus apparently drawing in air. Try an experiment and close off all but one of the suction lines and see if you are only getting air when one of them is open ... that could isolate the problem. My first thought was the same as yours, that your are pulling in air through the open skimmer either due to the low water level or a stuck weir door.

If you are getting air into the pump with any of the suction lines open, then the leak must be somewhere that is common to all the lines.

 

[flagirl]

I'm having a similar problem. When I shut off the main drain to operate the pool cleaner, I have air in the pump basket. I'm afraid there might be some blockage in the skimmer lines and I'm not looking forward to trying to check that out! I will lube the O-ring, just in case, but I doubt that's the source.

 

[Richard320]

Check the hose. I've also read that it can matter where put the swivel, if you have one.