Bubbles in return, pretty sure it is in discharge side

[bownut]

I followed the instructions for looking for a leak in the plumbing and pump. One of my pool returns bubbles a lot and the other not as much (it is further away from the pump). Because there was air in the pump basket, I stopped the pump, opened it, cleaned the O-ring, cleaned and reseated the drain plugs, capped it back and turned it back on. I bled out the filter until there was no air. Still bubbles. However, while I was in the area of all the plumbing I could hear gurgling water. I put my ear to the incoming plumbing, no sound. No sound in the pipe from the pump to the filter. But there is gurgling from the filter to the SWG and thereafter. What do I need to check now? I watched the video on Inyo Pools about finding air leaks, but they didn't deal with the discharge side of the system.

 

[Texas Splash]

How much and what size bubbles are we talking about? How is the pump strainer basket water level? Prime okay? Any air gap? If you weren't already aware, SWGs can product some small champagne-sized bubbles at times. Any other bubbles (air) introduced into the plumbing would have to be from the suction side (pool skimmer to the pump). If you had an air leak "past" the pump, you should see a pressurized leak and water coming out. The pool system simply cannot suck air "in" from the pressurized side while the system is on. Also keep in mind that depending upon your VSP's RPM, it can also generate some small bubbles, especially when at a lower speed.

 

[bownut]

I'll tell you about the last time that I checked it because I've turned off my pump again now that the water is super cold. We were at 57 degrees, so I brought all my chemical levels up just in case the warming continued, They are large bubbles, larger than you would find in soda. It isn't a consistent stream either. There are consistently bubbles, but the majority shoot out without regularity. I'm going to go back and specifically watch the strainer basket again. When I wrote above I didn't have bubbles in the basket, but when I shut the pump off a couple of days ago there was a lot of air in the basket. So, I'm going to turn it on and run it for 24 hours to see if air collects in the basket. Sometimes if it doesn't prime well, there will be air in the strainer, but I'll make sure I get a good prime and start without bubbles.

 

[duraleigh]

Check the water level in your pool to make sure you are not sucking air down the skimmer(s)

 

[flyinfitz1]

Mine gets air in from the SWG a lot of time. I can even see a little bit of dripping on the bottom side. I purge the filter of air every couple of days. Plan on re-plumbing once the rains stop here in CA.

 

[bownut]

Check the water level in your pool to make sure you are not sucking air down the skimmer(s)

The water level is mid way up the skimmer. I wish that were the issue.

 

[LotusRacerX]

Hey, I am having the same problem. No apparent air in the pump lid, no churning there. Bubbles are quite audible in the filter top, and the sides of the pool have what looks like carbonated bubbles in about a 3 inch strip around the pool.

I have never opened or separated any of the valve unions attached to the return pipe lines in the 12 years I've had the pool. Wondering if air could be sneaking in from there.

Weird thing is....if I turn the filter's multiport valve to "Recirculate", the bubbles go away, which makes me suspect it is something in the filter/multiport valve.
The bubbles CAN be heard in other modes, such as "Waste", "Rinse", and of course "Filter".

 

[LotusRacerX]

I had created a similar thread on this back in 2013.

https://www.troublefreepool.com/threads/54813-Can-a-Spider-Gasket-Multiport-Valve-cause-air-bubbles

Wish I had updated it with my solution. I know at one point I replaced my multiport valve's "Key, Cover, and Handle Assembly".
I may try that again.

 

[LotusRacerX]

Hey, fixed my problem yesterday, turns out. I had been suspecting that perhaps air was somehow being sucked in past the aging seals in my Polaris Booster pump while it was off.
(When I closed the valve that supplies the Polaris, bubbles ceased to come out the main jets. That did not make sense, so I had not reported my desperate attempt.)

Changed the seals, and put a new impeller while I had it open, and now the bubbles have not returned!

 

[LotusRacerX]

Bubbles are back. I lose again. I hate pool plumbing!

 

[LotusRacerX]

I have now changed the multiport valve (was worn flat on the spider gasket surface) and the booster pump and lines (new lines come with the polaris booster pump and the old ones were so sun rotted). Booster pump failed days after I redid the seals. It was 13 years old.

Well, my bubbles are now much less, maybe 1/4 of before, and only come into the pool while the booster pump is running.

 

[LotusRacerX]

Final solution found!!! Turns out my pump drain plugs, after 12 years, have cracked and broken up from the heat of many summers. Ordering replacements now and should finally have a bubble-free, if not trouble-free, pool.