Bubbles Building in the Pump Basket

[jim1504]

I have a good clearing of bubbles in the pump strainer basket when my filter is clean (pressure is usually 18psi) - not 100% but it has always been about 98% bubble free. As the filter gets dirty, more air goes into the pump basket. When the psi reaches about 22psi then the basket is about 85% bubble free (so a lot of air). There are no leaks in the pump. The seal is new and lubed on the strainer basket. I have noticed tiny air bubbles flowing from the impeller but I'm not sure if that is normal. My signature should list all of my pool info. Thanks for any help.

 

[spishex]

As your pressure increases your suction decreases, so if it's not apparent at clean pressure then it's probably not a suction side leak. I'd take it apart and check the diffuser o-ring. They go bad quickly on whisperflos, and if it's leaking water will try harder and harder to push past it as the filter gets dirtier. It ends up looking a lot like an air leak.

 

[jim1504]

Thanks very much for the help. I have already changed the diffuser O-ring. Could air be getting in through the mechanical seal?

As your pressure increases your suction decreases, so if it's not apparent at clean pressure then it's probably not a suction side leak. I'd take it apart and check the diffuser o-ring. They go bad quickly on whisperflos, and if it's leaking water will try harder and harder to push past it as the filter gets dirtier. It ends up looking a lot like an air leak.

 

[spishex]

No, you'd be losing water there. When you say you notice little bubbles coming from the impeller, where do you see them? Do you have clear pipe between the pump and filter or are you seeing this at the pool?

It could just be that there isn't sufficient water flow to fill the strainer when the pressure builds up. I've noticed that on a lot of Intelliflos (same housing as the Whisperflo) if you take them all the way down to low speed the air just doesn't get evacuated.

Have you tried changing/lubricating the lid o-ring? It's also possible that as the suction decreases the lid isn't pulled down as tight and small cracks in the o-ring start to leak.

 

[jim1504]

Thanks again for the help! I notice the bubbles slowly rise from the chamber where the impeller is (can see through the glass top pump motor lid. A leslies tech is the one who actually pointed it out to me and suggested the mechanical seal (it looked ok). The pump assembly was tested to 40 psi of pressure with no leaks.

Do you think possibly that my 3/4 hp pump has become less powerful over time? It worked fine in the past. I was told by Leslies that 3/4hp was too small for my pool. Thanks again.

No, you'd be losing water there. When you say you notice little bubbles coming from the impeller, where do you see them? Do you have clear pipe between the pump and filter or are you seeing this at the pool?

It could just be that there isn't sufficient water flow to fill the strainer when the pressure builds up. I've noticed that on a lot of Intelliflos (same housing as the Whisperflo) if you take them all the way down to low speed the air just doesn't get evacuated.

Have you tried changing/lubricating the lid o-ring? It's also possible that as the suction decreases the lid isn't pulled down as tight and small cracks in the o-ring start to leak.