Where is my leak ..

[Phillbo]

When my pump kicks in I get a couple real big bubbles out the return lines.. Nothing major but enough to tell me I have a leak allowing air into the system while the pump is not running...

The backwash valve is new as is the o-ring in the basket just before the pump.

[Poconos]

I'm not surprised that air gets in the system without the pump running. Happens to me sometimes from my solar heater in the back field. Consider the water in the filter, pump, pipes etc is trying to seek the level of the pool water it pulls a pretty good vacuum at the highest point whick would usually be the top of the filter and a valve if it happens to be there. My high point is the solar heater about 10' above the pool. Under pressure whatever is leaking air just seals. Trying to find something like a slow air leak can be a dog and I don't have any easy ideas. Sorry. Maybe someone else does. I just live with it.
Al

[CarlD]

I'm not surprised that air gets in the system without the pump running. Happens to me sometimes from my solar heater in the back field. Consider the water in the filter, pump, pipes etc is trying to seek the level of the pool water it pulls a pretty good vacuum at the highest point whick would usually be the top of the filter and a valve if it happens to be there. My high point is the solar heater about 10' above the pool. Under pressure whatever is leaking air just seals. Trying to find something like a slow air leak can be a dog and I don't have any easy ideas. Sorry. Maybe someone else does. I just live with it.
Al

Me too. My system has too many connections to ensure NO air passing.

[mwsmith2]

The number of connections shouldn't determine wether you have an air-tight system. Good thing cars or space shuttles aren't designed like that! Sucking air in is hard on the pump impeller (cavitation) and should be avoided at all costs.

OP: check your jandy valves on the suction side. Usually the o-rings in there harden and go bad after several years. You can use a 2' - 3' length of 1/2" PVC pipe as a stethoscope to listen for bubbles. Put one end to the pipe after the valve and one end to your ear. If you hear gurgling, you've found the culprit. If not, move on to another. If you don't hear any gurgles on the suction side, the air leak may be where the suction pipe joins the pump strainer, or the pump lid may be leaking. If it is an o-ring or pump basket cover seal leaking, replace the o-ring and be sure and use silicone lubricant when you put it back together, that'll ensure a leak-free seal. Also be sure not to pinch the o-ring when putting the jandy back together, that's easy to do with the big o-ring for the body.

Michael

[Phillbo]

The pump is not sucking air .. The basket / bowl just prior top the pump stays full of water to it has to be down stream of the pump. I'll check the seal on the guage / valve on top of the filter.

[Poconos]

Something else I just thought of. You do mention the filter has a top mount valve. Ever look at how much the filter body expands or deforms when under pressure? Quite a bit. My Hayward uses a clamp ring to hold the valve assembly to the body and I could easily suspect that under pressure you have no leak but under a partial vacuum you may. Also remember, doesn't take much of a leak to let air in compared to water.
Al
Sidenote: That solar thing in my field has something like 30 joints. Black poly, bib connectors and hose clamps. I've pressure tested the sucker with compressed air up to 40-50 PSI as I remember and no leaks. Give it a little time, temperature swings and pressure cycles and something will always loosen and leak air under a vacuum.

[mwsmith2]

With the heated water in the panels I think it's more likely that you have outgassing in the water than an air leak.