Earlier this year we had a jet that was spewing air bubbles. We also noticed the flow over the hot tub was a lot less. I did my research and determined there was a leak somewhere. I followed the steps (here I think) and couldn't figure it out. I called the pool company to come check it out. They came and couldn't find a leak either but he did a backwash and said that fixed the problem. OK??? Anyway, a month after he came, I backwashed again. Then two weeks later we noticed the problem again. When I backwash, I go through 3 backwash cycles. I decided to backwash again and see what happens. I did the first cycle and all three problems (bubble in pump, air bubbles from jet & low flow over waterfall) were gone. I stopped. Yesterday (about 10 days later) I noticed it happening again. This morning there is almost no flow over the waterfall. I need advice.....
Air bubble in filter pump
- Thread starter williamsfab5
- Start date
- Jun 22, 2014
- 48,347
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
Well, most often when we see air bubbles, we think suction side leak that is pulling air. Most of the time. 
You seem to have exhausted all of that to the point of having a leak company inspect as well. In addition, you have low water flow going out. I'm assuming your pump basket stays full of air correct? Water level good and basket O-ring lubed? Now the reason I say all of this is that because in my pool system, I see something similar and perhaps it may relate to you as well. When my filter is clean with no restriction, flow is always good and pump basket full of water. I started to notice that at times my pump basket water level would drop slightly because of more air, and I would see some champagne bubbles from a couple return jets. Even though my system is relatively new, I exhausted all of the suction side leak items as well. I later come to the realization that the suction pressure might sometimes cause some outgassing because of the intense churning of the water. In addition, if my filter started to get dirty and pressure increase, I would see more air in the pump basket and air bubbles. I also have a separate waterfall stub-out for aeration and fun, and when I have that on (pressure side) I see more bubbles - again I believe outgassing of sorts at the connections & split-offs. But in any case, when my filter becomes dirty and pressure increases, I think it creates more back-pressure against an already strong pump water pull. This causes lots of churning and I believe more outgassing in my system.
Sorry for the long version :blah:, but perhaps you still have some restriction going on somewhere in your system. If there's a restriction, water gets jammed-up from all the pressure and can cause a couple different symptoms. Since your pool is an estimated 4 years old, have you ever done a thorough sand deep clean as outlined on the TFP Deep Cleaning a Sand Filter page? All the backwashes in the world won't help if the sand has become channeled or compacted to the point it's not allowing water to flow efficiently though the sand. I'd give that a shot to see what type of effects if may have. It would be good to know water can flow easily and efficiently out of your filter before going backwards to the suction side you already invested so much time and $$ to. Let us know if you try it and the results.
You seem to have exhausted all of that to the point of having a leak company inspect as well. In addition, you have low water flow going out. I'm assuming your pump basket stays full of air correct? Water level good and basket O-ring lubed? Now the reason I say all of this is that because in my pool system, I see something similar and perhaps it may relate to you as well. When my filter is clean with no restriction, flow is always good and pump basket full of water. I started to notice that at times my pump basket water level would drop slightly because of more air, and I would see some champagne bubbles from a couple return jets. Even though my system is relatively new, I exhausted all of the suction side leak items as well. I later come to the realization that the suction pressure might sometimes cause some outgassing because of the intense churning of the water. In addition, if my filter started to get dirty and pressure increase, I would see more air in the pump basket and air bubbles. I also have a separate waterfall stub-out for aeration and fun, and when I have that on (pressure side) I see more bubbles - again I believe outgassing of sorts at the connections & split-offs. But in any case, when my filter becomes dirty and pressure increases, I think it creates more back-pressure against an already strong pump water pull. This causes lots of churning and I believe more outgassing in my system.Sorry for the long version :blah:, but perhaps you still have some restriction going on somewhere in your system. If there's a restriction, water gets jammed-up from all the pressure and can cause a couple different symptoms. Since your pool is an estimated 4 years old, have you ever done a thorough sand deep clean as outlined on the TFP Deep Cleaning a Sand Filter page? All the backwashes in the world won't help if the sand has become channeled or compacted to the point it's not allowing water to flow efficiently though the sand. I'd give that a shot to see what type of effects if may have. It would be good to know water can flow easily and efficiently out of your filter before going backwards to the suction side you already invested so much time and $$ to. Let us know if you try it and the results.
- May 3, 2007
- 17,125
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
If you see air in the pump basket as the filter gets dirty but then it clears up after the filter gets cleaned, then I would suspect the pump lid gasket. The reason is that as a filter gets dirty flow rate goes down which reduces the suction in the pump basket so the lid seal may not seal as well as when the filter is clean and suction is high. If you have already tried lubing the pump lid and drain plugs, then you might try replacing the pump lid gaskets. Also, make sure the lid is tightened to the stops.
Thanks. I didn't know what a sand filter was so I went and watched the videos. I don't have this type of filter. Inside my "egg" we have the 8-10 paddle type things. I do completely remove them and wash them before and after each swim season.
I don't know the official names, but if you are referring to the O-ring inside the pump lid, that was one of the steps I went through in the beginning. I replaced it already.
I like the line of thinking mas985 went down. Continuing with that logic, maybe try getting a smoke wand and holding that near the pump intake and other plumbing parts before it (I've never tried it but seems like it could work?). If some of the lines are underground you might try dumping a five-gallon bucket of water near those and see if it clears up the bubbles.
Update: I've just backwashed one cycle.... no more air bubble in pump and overflow on hot tub is back to normal. Still.... there must be a problem somewhere.....
- Jun 22, 2014
- 48,347
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
Ahhhh Rats! You have a DE filter. How'd I miss that? 
Disregard the whole deep clean thing. Duh. Aside from standard items on the Pool School - Suction Side Air Leaks page, perhaps ensure there's no obstruction in the line. Any chance a critter got past your skimmer basket and into the line? Also, when you replaced the O-ring at the pump basket, did you lube it with pool silicone lube?
- - - Updated - - -
Another trick for above ground suction side leak checks besides using a water hose, smoke, or shaving cream, is trying some plastic wrap. It's clean and fairly reliable against the equipment surfaces. Maybe check around any suction side valves.
Disregard the whole deep clean thing. Duh. Aside from standard items on the Pool School - Suction Side Air Leaks page, perhaps ensure there's no obstruction in the line. Any chance a critter got past your skimmer basket and into the line? Also, when you replaced the O-ring at the pump basket, did you lube it with pool silicone lube?- - - Updated - - -
Another trick for above ground suction side leak checks besides using a water hose, smoke, or shaving cream, is trying some plastic wrap. It's clean and fairly reliable against the equipment surfaces. Maybe check around any suction side valves.
There's always a chance a critter got in. How can I check for an obstruction. Yes, the o-ring was lubed.
How do I use the plastic wrap to check for a leak?
How do I use the plastic wrap to check for a leak?
- May 3, 2007
- 17,125
- Pool Size
- 20000
- Surface
- Plaster
- Chlorine
- Salt Water Generator
- SWG Type
- Hayward Aqua Rite (T-15)
Even lubing the lid gasket may not be enough if the gasket has a crack in it. Did you remove the gasket and look carefully for any cracks?
- Jun 22, 2014
- 48,347
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
You could try sticking a water hose from the pump inlet and aim the water towards the pool skimmer (basically water going backwards). Wrap the hose with a rag as well inside the pump basket. You're just checking to ensure water can flow freely. As for the plastic wrap, simply find a suspect are like a joint or valve and wrap the plastic all round that section or part. It can be handy on days when it's windy and smoke won't work, or around parts that you can't really get water to easily. You're just trying to smother a leak area with plastic to see if there's any different in air or water level in the pump basket.
thanks Texas for the idea on shaving cream - I'll have to try that next time - never heard of that one.
I tried plastic wrap before but like the article Texas linked to (...and thank you for that too) said, slow and painstaking. I took a few 1' sections of cling wrap and stuck it near/on the pipes to see where it stuck.
I tried plastic wrap before but like the article Texas linked to (...and thank you for that too) said, slow and painstaking. I took a few 1' sections of cling wrap and stuck it near/on the pipes to see where it stuck.
- Jun 22, 2014
- 48,347
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
Oh, and don't forget to check your pump drain plugs! Very small O-rings there as well.