SCWD pulling air in

[dvskin]

Hey guys, finally got my 80 rimless wet. I have a slight problem with my SCWD though. Every time it "switches" I get a noise of air being pulled in, well bcuz it is being pulled in, lol. There is a dbl union ball valve before the SCWD, and I have tried both slip and threaded fittings off the ball valve. I have also put Teflon tape on the top of the SCWD itself. No change, still getting the air bubbles. Is there anyone with any experience with the 1" version of the SCWD, and has any solutions?

Thanks
Chad

 

[AZDesertRat]

How is the pump feeding the SCWD plumbed? Your air could be the fault of the pump and/or the way it is plumbed. Any photos of the rest of the plumbing arrangements both in and out?

 

[dvskin]

Not much more than this. The output of the pump goes straight to the SCWD.

 

[AZDesertRat]

How is the suction side of the pump fed? How many fittings are there which could cause restrictions and cavitation in the pump which would lead to air bubbles. Have you tried slightly closing the ball valve on the discharge side of the pump to add a little head? If the bubbles go away this may be the problem. Its best to plumb the suction side of a pump in a straight shot when possible so you have no suction head losses.

 

[dvskin]

It is plumbed to an elbow. But I upsized the pipe diameter from 3/4" to 1.5". It seemed to have stopped for the most part, I believe there was air trapped in the top of the SCWD. I think the design would benefit from a bleeder valve right on top of the SCWD and I think I'm gonna install one

 

[dvskin]

Aggravated now. I haven't even put salt in the system yet, and the SCWD has stopped switching outlets. I'm gonna take it all apart (again) and check everything. If this keeps happening, I'm gonna just get rid of the SCWD anyway. Maybe look into an oceans motions.

It sucks, cuz I ran the 3/4" version for 2 years flawlessly on my 65. I ASSumed that this one would be hassle free.