When is it time for a new cartridge filter? High PSI

[AB]

Hello,

I have gotten into a cycle where my pump pressure gets up around 30-32 psi and then it is time to clean the cartridge filter. I hose it down and then it goes down to 20 psi. Then 2 weeks later it is back to 30-35!

My pool is crystal clear, pump runs about 10 hours a day, and I have shocked it to ensure there is no FC. Since the pressure keeps going up, is this an indication a new filter is required?

We have been in the house for 2.5 years and I am not sure of the maintenance of the filter before that point.

When you replace a filter, is it strictly on a yearly, 5 yearly, etc schedule... or is it time to replace it when you get high PSI ratings that wont go down with a clear pool?

CYA is around 50, TA, PH at normal levels.

Thanks, Aaron

 

[frustratedpoolmom]

You shocked it to make sure there is no FC? You mean CC, yes?

Assuming your normal levels are in line with our recommendations, I would say your guess is a good one. How many sf is the filter?

Cartridge Filters can last 4, 5, 6 years depending on their use (were they used to clear a swamp, etc.) and how they were maintained (cleaning routine - see Pool School article on cleaning cartridges). If they weren't used for a swamp and were cleaned and stored properly yes it extends their life. I would say your's is probably done.

 

[AB]

Yes - sorry meant to say no CC. Whoops!
My other levels are ph = 7.5, TA = 110, CH = 220.

I'm in Houston, so I don't close the pool for the winter - so the cartridge filter stays in year round.

Thanks for the quick reply - so generally a high PSI that does not stay down after filter cleaning (assuming pool levels are good) is the way to tell if you need a new filter?

 

[frustratedpoolmom]

Yes.

 

[AB]

I just wanted to update you, I soaked the filters in muriatic acid for 45 min and the psi went down from 35 to 16! Will keep an eye on it and let you know.