Air bubbles from old filter cartridge?

[Jim H]

Hi all. Getting air bubbles in my pool- researched all the possibilities. However my filter cartridges are overdue for replacing, which I am doing this weekend. My pool guy insists that this can be a cause of air bubbles- I've looked online to confirm this and can not find this anywhere. Once I replace the filters I'll obviously have an answer, but I was wondering if anyone has ever heard of this?

 

[Jimrahbe]

Jim,

I doubt that "bad" cartridges could cause air bubbles.. Maybe if they were so bad that they barely let any water pass through, but I suspect that is not the case.

My cartridges are 7 years old and show no signs of any damage. I fully expect to get 10 or more years out of them. How old are yours???

Unless a cartridge is visually damaged, it should need to be replaced.

What is your filter pressure?

Are you sure the bubble are not from your salt cell??

What type of pump do your have? Single speed, 2-speed, or variable speed??

Thanks,

Jim R.

 

[Jim H]

Jim,

I doubt that "bad" cartridges could cause air bubbles.. Maybe if they were so bad that they barely let any water pass through, but I suspect that is not the case.

My cartridges are 7 years old and show no signs of any damage. I fully expect to get 10 or more years out of them. How old are yours???

Unless a cartridge is visually damaged, it should need to be replaced.

What is your filter pressure?

Are you sure the bubble are not from your salt cell??

What type of pump do your have? Single speed, 2-speed, or variable speed??

Thanks,

Jim R.

They are 6 years old- life of the pool. Even with cleaning they are discolored but no sign of damage. Pressure is only at 10-15 but I have the pump running low at 24 GPM's since I run it 24 hours/day. When I open the pressure valve and leave it open until water starts coming out then the bubbles in the return go away. After about 30 minutes they reappear. I haven't turned on the salt cell yet so do not think it could be that.

 

[Newdude]

Even with cleaning they are discolored but no sign of damage

Then they are fine. I gave mine a TSP and MA bath at the end of each season to restore them to ‘tight-y white-y’ clean, but the color did nothing for actual cleaning abilities.

When I open the pressure valve and leave it open until water starts coming out then the bubbles in the return go away. After about 30 minutes they reappear

So you have either air getting in the system or a leak on the suction side. The two most common reasons to suck air are the pump basket O-ring needing to be lubed/replaced and a weir door not functioning properly / intermittently stuck. Make sure all the doors freely open/close and that the water level is half way up the faceplate. If either are off you can suck air which gets trapped in the filter. With enough air in the filter you start shooting bubbles.

If it’s not that, go after the pump seal, first by lubing and then replacing.

If *that* doesn’t work then you probably have a leak and we will address further.

 

[Jimrahbe]

Jim,

My filter pressure is about 2 lbs. when running at a low RPM (1200). When I open my vent valve, water comes out within a second or two..

Other than cost, it can't hurt to replace the cartridges.. and if nothing else, it will eliminate them as the problem. Please let us know if that solves your issue.

I suspect that you have a small suction side air leak, but I have been wrong about 100 times this morning alone..

Thanks,

Jim R.

 

[Jim H]

Thanks for the advice. I know the water level is fine I checked that already. I already checked the O ring too and re-lubed it just in case but that seal seems pretty tight. The doors seem to be opening and closing properly on casual inspection but I will take a closer look tonight. The pump itself is only a year old But I will keep you updated. Thanks again. My ultimate fear is of course that I always go to worst case scenario and worry that there’s a leak in the plumbing underground.

 

[Newdude]

My ultimate fear is of course that I always go to worst case scenario and worry that there’s a leak in the plumbing underground

Of course !!! Lol. It does happen but it’s *hopefully* a simple more common problem.

 

[Jim H]

SO I've read up on tons of information on all the causes of air bubbles in the returns and have done trouble shooting and everything that is suggested- skimmers, doors, o rings, drains, etc. Still no help. I am to the point where I have to consider the disaster of checking the underground plumbing. My question: what if I don't? So I know air bubbles are not normal but how much damage is it doing to my system? And if so, the cost analysis to me seems to be to just let things ride. Even if I have to replace my pump more frequently and flow is not ideal/less efficient, I have to weigh that against the thousands of dollars and upheaval/damage to lawn, pavers, etc. for them to potentially dig up and find the leak. Anyone out there has just let their air bubbles ride?

 

[ajw22]

If your pump basket does not go dry and your pool is not leaking water then air bubbles are not a big concern.

Ignoring an underground pool water leak can lead to the eventual fix being much more expensive.