Pump pressure rising 10 psi over one week???

[kodiak1120]

I've had an ongoing issue where the pressure in my DE filter will slowly rise over the course of a week or two. When I backwash, the pressure goes back to normal, but then in a week or two goes back up gradually. Normally, my PSI after a backwash is about 10 psi or 11 psi. By about a week or two, it's up to 20 psi.

I had a suction side leak at a jandy valve, that I have since replaced. Before replacing the valve, I assumed the problem was due to air getting into the filter, causing the pressure to rise. I now know there is zero air getting in the suction side, based on the fact that I have no bubbles in my skimmer basket, the skimmer basket stays fall when the pump is off and does not lose prime, and when I open the bleeder valve on top of the filter I get only water and no air.

My chlorine levels are good and I have zero CC. The water is crystal clear and looks great.

I can only figure that something is clogging the filter but I can't figure out what. Any help?

 

[pabeader]

When you say levels are good, can you post them, please? Also, which test kit are you using to test the levels?

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You are filtering out something, probably algae. That is what DE filters do well but it's a double edge sword. It filters so well that you need to 'clean' it more often. If you maintain your FC level at the proper amount, the algae won't be able to get started and your filter should have less to collect.

 

[Jimrahbe]

K,

You do not have a mechanical filter issue, you have a chemical issue, no matter how clear your water is... By the time you can see the algae it is too late.

As Bob says above, your filter is filtering out something and the most likely suspect is algae.

I suggest that you run an Overnight Chlorine Loss Test or OCLT... Here is how... Overnight Chlorine Loss Test

Thanks for posting,

Jim R.

 

[kodiak1120]

I have the K2006 kit. When I checked last week, my FC was 7.0, my CC was 0, PH was 7.6, TA was 80 and CYA was 100. I don't see any evidence of algea in my pool. Also, this has been going on since last summer. As I mentioned, I assumed it was because air was getting in the filter and getting trapped, but I've ruled that out. Could it be my pump motor? The motor is on its last legs, but I thought that would cause low pressure, not high pressure.

 

[Jimrahbe]

K,

With a CYA of 100 your minimum FC is 8 and you should be running an FC of 12. That assumes your CYA is actually 100 which is as high as the test reads, so it could be much higher.

I can't think of any mechanical problem with the filter or the pump that will cause your problem.

Thanks,

Jim R.

 

[tstex]

K,

You do not have a mechanical filter issue, you have a chemical issue, no matter how clear your water is... By the time you can see the algae it is too late.

As Bob says above, your filter is filtering out something and the most likely suspect is algae.

I suggest that you run an Overnight Chlorine Loss Test or OCLT... Here is how... Overnight Chlorine Loss Test

Thanks for posting,

Jim R.

+1 on this and similar...if truly a CYA of 100, your FC is way too low and you have algae. But, your FC level is high enough to kill it from a visual perspective, but once killed, it's killing your filter...that fact that it builds up over time is perfect evidence...

Chemistry issue, not a filter issue OCLT is in order

 

[Mike1162]

You mentioned back washing the filter, when was the last time you disassembled & gave it a thorough cleaning?
Is the filter the grid or finger style?

 

[kodiak1120]

You mentioned back washing the filter, when was the last time you disassembled & gave it a thorough cleaning?
Is the filter the grid or finger style?

I just did that a week or two ago when I was trying to figure this out. I took everything apart from the pump to the filter grids and make sure there were no blockage issues.

 

[lamerem]

SLAM time.....

DE building pressure, algae issue. Have you done an overnight chlorine test?