No Prime From Main Drain

[BamaUSAF]

With 3 way diverter valve on Main Drain or a combo of Main Drain and Skimmers the pump won't prime - with just skimmers it primes - any chance this is the diverter itself and not an air leak in plumbing going to main drain?

 

[Jimrahbe]

Bama,

I can't see how it would be possible to have an air leak in a pipe that is basically filled with water..

My guess is it is a diverter valve O-Ring issue.

Even if I'm wrong, (about 100 times a day) it would make the most sense to start with rebuilding the Jandy valve.

Thanks,

Jim R.

 

[1poolman1]

With 3 way diverter valve on Main Drain or a combo of Main Drain and Skimmers the pump won't prime - with just skimmers it primes - any chance this is the diverter itself and not an air leak in plumbing going to main drain?

As Jimrahbe said, start with the Jandy valve, especially the stem O rings. If the valve is older, I always replace the rings, add a bit of lube and then a couple of wraps of Teflon tape and a bit more lube on that. Trying to pull water from the bottom of a pool increases the "suction" in a system and any small air leak, like a the stem O ring of a valve, becomes a larger issue.

 

[Newdude]

Ever crack a straw shoving it into a fast food drink cup? Just like that. It doesn't take much of a leak to suck all air and no drink/water

 

[BamaUSAF]

Thanks all - turned out it had junk (maybe 12 years worth of junk) and - was causing the gasket not to seal on that port -, even though got it working, cut it out and just installed two ball valves (one for skimmers and one for main drain) - seems simpler in my non pool brain

 

[bradgray]

Thanks all - turned out it had junk (maybe 12 years worth of junk) and - was causing the gasket not to seal on that port -, even though got it working, cut it out and just installed two ball valves (one for skimmers and one for main drain) - seems simpler in my non pool brain

Ouch.

I would have for sure just rebuilt the 3-way.

Those ball valves can't be repaired and they all tend to ultimately seize up.

Fingers crossed you get lucky and they give you years of problem free operation