Pentaire Cartridges

[gorji]

Is it time to replace my cartridges? Ive had my Pentair size 75 cartridge for my 9000 gallon fiberglass pool. Recently after cleaning them, the pressure I get when installing them is 10 psi. Within 5-10 hours, the pressure icnreases to about 20 psi. My pool is really not dirty; I have a feeling that the filter is clogged with either calcium (my calcium was on the higher end). I use the Taylor kit for measurement. I use the TFP method of using bleach only.

The cartridges are about 4-5 years old but living in the NE they are used only for about 5 months a year.

I clean them by placing them in a bin, add dishwasher detergent then let them soak for 24-48 hours. Then I rinse with garden hose cleaning until nothing but water comes out on the bottom.
The pool chemistry is all within order. Even the CYA is 40.

Should I replace them?
Any other advice will be appreciated.

 

[bobodaclown]

Have you read this:
http://www.troublefreepool.com/threads/4224-Re-How-to-clean-a-cartridge-filter

http://www.troublefreepool.com/content/144-maintenance-and-cleaning-of-pool-filters

Great info...

 

[pooldv]

As long as you are sure you aren't having early stage algae bloom. Has your FC level dropped below the minimum for your CYA this spring? Chlorine CYA Chart One of the first signs of an algae outbreak is a rapidly clogging filter and higher chlorine consumption.

If you do get a new cartridge, I recommend the Pleatco filters. They work better for me than the Pentair OEM filters.

 

[scott39]

I had a similar experience last year. Ended up replacing with Pleatco.

The discharge pressure with the clean Pleatco cartridges was lower than clean OEM cartridges.


Sent from my iPhone using Tapatalk

 

[mas985]

Sounds like an algae bloom to me.

If the filters were calcified, the pressure would be always high not just after some run time. The fact that the pressure goes from a low pressure to a high pressure means you are filtering something out of the water and it usually is an algae bloom that causes this.

After cleaning, does the pressure go back down to 10 PSI?

 

[bobodaclown]

Time for a SLAM.

 

[gorji]

WOW Great responses. No algae in the pool but the pool Cl was a bit low before I posted this which I corrected. I think that may be the answer. Shame on me for not thinking that.
The pressure goes down after washing them. I did do an acid wash yesterday as recommended by the links above. The pressure went to 10 from 20. 8 hours later the pressure was up to 13.

I appreciate the help being offered. Thank you.

 

[mas985]

No algae in the pool but the pool Cl was a bit low before I posted this which I corrected.

Note that algae is not always visible at the start but can still clog up a filter.

 

[dschribs]

I wouldn't use anything but Pleatco for my filter.

I ended up buying two sets. One to clean up the pool and one set for the remainder of the season.

 

[pooldv]

+1 to algae not being visible in the pool at first.

Here is the life cycle of an algae bloom as you would see it:
chlorine consumption increases due to increased organic matter
filter starts to clog due to algae reproducing and being killed by chlorine
pool water starts to cloud as algae level increases and chlorine consumption increases
pool water turns green when there is more algae than chlorine to kill it
somebody posts on TFP "HELP, my pool is a Swamp!"

This is why it is important to test regularly (i won't say daily) to monitor chlorine level and notice if the increased consumption is based on higher temps, more sun, more swimming, etc. If the higher demand can't be justified then beware! Always make sure that chlorine is above the minimum for your CYA level on the Chlorine CYA Chart and you will never have algae.