Pentair CCP420 Cartridge Filter Drains Quickly After Shutoff

[Flubadub]

17 year old pool and equipment. A&A in-floor cleaning system. Whisperflo Pump motor recently replaced. Recently started blowing large amounts of air through pop up heads on startup.

The filter tank starts draining (almost as if the air relief valve was open) as soon as the filter is turned off. There are no visible leaks anywhere in the system and no bubbles in the strainer when running. After shutoff, water appears to be running backwards through the strainer into the pool. Filter o-rings and relief valve recently replaced. Local pool repair tech with a good reputation replaced an in-line valve (small, with a clear top), but left stumped as to why the filter was draining.

I'm concerned that the massive air released through the pop-up heads is going to cause damage. Any thoughts on what is happening here?
Thanks!

 

[ajw22]

Welcome to TFP.

You have a leak someplace that is sucking in air when the pump is off. Could be in a pipe joint or could be an O ring in a valve or union.

@proavia will need to opine if the air will damage your heads. I don’t think they will.

 

[proavia]

Welcome to TFP!

As Allen stated, you have an air leak somewhere.
What does/did the lid/O-ring on the heater go to?

The air should not damage the popups in the short term. But you really should find and fix the air leak for the good of all your equipment in the long term.

A good starting point would be the O-rings on the leafvac and pump basket lid. Clean the O-rings and their mating surfaces really well and then lube the O-rings with silicone lube (like magic lube II, not magic lube I).

When you shut the pump off, do you see any water spit out anywhere - even the tiniest bit?

 

[Flubadub]

As Allen stated, you have an air leak somewhere.
What does/did the lid/O-ring on the heater go to?

The air should not damage the popups in the short term. But you really should find and fix the air leak for the good of all your equipment in the long term.

A good starting point would be the O-rings on the leafvac and pump basket lid. Clean the O-rings and their mating surfaces really well and then lube the O-rings with silicone lube (like magic lube II, not magic lube I).

When you shut the pump off, do you see any water spit out anywhere - even the tiniest bit?

Thanks for the welcome!...and the tips.

The loose lid and o-ring on the heater are extras for the pump basket.

I cleaned the leaf vac and pump basket mating surfaces and installed new o-rings a few days ago...they appear to be air tight. The pump basket lid is clear and no bubbles enter the basket when the pump is running.

There are no visible drips, leaks or spurts while starting, running or stopping. I can't see what's going on inside the heater (which hasn't been used in over 10 years) but the problem exists whether it's bypassed or in line. Plus, it's on the pressure side.

I installed a new 1.5hp motor about a month ago along with seals, gaskets, o-rings and impeller. The old seal in the seal plate had been leaking for a long time. The system was blowing air out of the pop-ups before the motor replacement but the problem has gotten significantly worse since. There are no wet-side/dry-side water leaks.

The biggest clue IMHO is how quickly the filter drains, almost as if the air relief valve is open. Speaking of which, I installed a new one yesterday to no effect.

 

[proavia]

The loose lid and o-ring on the heater are extras for the pump basket.

Put the lid/O-ring in a plastic bag in the garage to protect it from the AZ sun.

I cleaned the leaf vac and pump basket mating surfaces and installed new o-rings a few days ago...they appear to be air tight. The pump basket lid is clear and no bubbles enter the basket when the pump is running.

Did you lube the clean O-rings with the proper lube prior to reinstalling them into the lids?

Chances are if there is a significant increase in the bubbles after you worked on the system, it is something you did. Review the entire process and identify/fix the issue.

 

[Newdude]

There are no visible drips, leaks or spurts while starting, running or stopping.

Can you hear it sucking air upon shutoff ? If so does it pssssssssssssst or glug glug glug ?

There are no visible drips, leaks or spurts while starting, running or stopping

Suds it all up while running with a dish soap / water mix.

 

[Flubadub]

Again, thanks for your suggestions. The clamp o-ring appears to be the culprit. It doesn't leak, drip or spurt, but it is definitely letting air in. I replaced it with an Amazon $13.99 special which spurts a little on startup but doesn't leak or drip once running. It completely stopped the air leak. That didn't make sense to me, so I put the old clamp o-ring back in and once again, the tank started draining immediately upon shutoff. I put the new o-ring back in and no more air leak.

I still don't understand how a seal that doesn't let pressurized water out can let so much air in. Anyway, I'm going to buy a genuine, $45 Pentair o-ring and call it fixed.

 

[1poolman1]

17 year old pool and equipment. A&A in-floor cleaning system. Whisperflo Pump motor recently replaced. Recently started blowing large amounts of air through pop up heads on startup.

The filter tank starts draining (almost as if the air relief valve was open) as soon as the filter is turned off. There are no visible leaks anywhere in the system and no bubbles in the strainer when running. After shutoff, water appears to be running backwards through the strainer into the pool. Filter o-rings and relief valve recently replaced. Local pool repair tech with a good reputation replaced an in-line valve (small, with a clear top), but left stumped as to why the filter was draining.

I'm concerned that the massive air released through the pop-up heads is going to cause damage. Any thoughts on what is happening here?
Thanks!
View attachment 627179View attachment 627180

Air going through the system won't hurt anything. The same thing happens on pools with solar panels when the solar starts if the panels drain properly.
Something that was done is now allowing air into the system. Not unusual on a pool system that age. It doesn't take much, especially if the filtration system was disturbed by a repair.
Watch for a water leak, especially below that new motor as that would be the first place I would look.

 

[proavia]

Did you tighten the filter clamp so the spring is fully compressed?
The coils on the spring need to be touching one another.

 

[Victor Newman]

I don't mean to hi-jack the thread....but now that the problem is fixed....We just now bought a Pentair 160301, 420 sq.f., for our 13K gallon inground pool and it works fine. Noticed in post #1, air coming out of pop-up heads. What is that please IDK ?

 

[Newdude]

Noticed in post #1, air coming out of pop-up heads.

In floor cleaners, basically sprinkler heads in the floor that push debris to a suction port.

 

[Victor Newman]

10-4 and thanks.......