Filter pressure after transition to cellulose fiber

[AceHigh]

Hi all, new here and starting to dig into all the great knowledge here... Really glad this site exists!

I have a question - I learned how to do a full clean of my Pentair fns plus 48 de filter on YouTube and decided to do the recharge with cellulose fiber this time around. (Wanted to do perlite but couldn't find any in my area)

But after the full clean and recharge... the pressure on my filter is only like 1 or 2 PSI. Shouldn't it be higher? Before the clean it was running around 20 PSI (I believe it was filled with DE, not sure though. Just bought the home.)

I bled air from the release valve when I restarted so I don't think air is the problem... And there aren't any obvious leaks or anything.

Any thoughts here? Or am I just incorrect in thinking that the pressure should be higher?

Thanks all! Looking forward to taking charge of my own pool maintenance rather than paying others!!

 

[1poolman1]

Hi all, new here and starting to dig into all the great knowledge here... Really glad this site exists!

I have a question - I learned how to do a full clean of my Pentair fns plus 48 de filter on YouTube and decided to do the recharge with cellulose fiber this time around. (Wanted to do perlite but couldn't find any in my area)

But after the full clean and recharge... the pressure on my filter is only like 1 or 2 PSI. Shouldn't it be higher? Before the clean it was running around 20 PSI (I believe it was filled with DE, not sure though. Just bought the home.)

I bled air from the release valve when I restarted so I don't think air is the problem... And there aren't any obvious leaks or anything.

Any thoughts here? Or am I just incorrect in thinking that the pressure should be higher?

Thanks all! Looking forward to taking charge of my own pool maintenance rather than paying others!!

Its not unusual at all for the pressure to be much less with cellulose fiber, as long as the correct amount was added. First started using it in 1992-1993 when it first became available for pools. Was told by the manufacturer's rep to expect very different pressure-gauge readings. Would watch the pressure go down as the fiber was added to the skimmer and fill the filter. The proper amount for your filter is one full scoop in an orange DE scoop as in the picture. Works everytime.

Be aware that if you didn't do a soak of the grids to remove any oils on them (there's always oils in a filter) you will have to do a backwash/clean out of the fiber rather quickly. The rep warned me of that and its very true, so don't be disappointed if it happens to you, its normal for the product. The cellulose will soak up any oils in the grids and turn into a gooey mess the first time if oils weren't removed or new grids installed.

That's why so many in my area immediately hated the product, which was fine with me as they gave me what wasn't used. Servicing many commercial pools at the time, it saved me quite a bit of money on a product I wouldn't do without. I went from using 400# of D.E. per month to 1- 25# bag (which is the equivalent of 200# D.E.) per month and had water that sparkled

 

[AceHigh]

Its not unusual at all for the pressure to be much less with cellulose fiber, as long as the correct amount was added. First started using it in 1992-1993 when it first became available for pools. Was told by the manufacturer's rep to expect very different pressure-gauge readings. Would watch the pressure go down as the fiber was added to the skimmer and fill the filter. The proper amount for your filter is one full scoop in an orange DE scoop as in the picture. Works everytime.

Be aware that if you didn't do a soak of the grids to remove any oils on them (there's always oils in a filter) you will have to do a backwash/clean out of the fiber rather quickly. The rep warned me of that and its very true, so don't be disappointed if it happens to you, its normal for the product. The cellulose will soak up any oils in the grids and turn into a gooey mess the first time if oils weren't removed or new grids installed.

That's why so many in my area immediately hated the product, which was fine with me as they gave me what wasn't used. Servicing many commercial pools at the time, it saved me quite a bit of money on a product I wouldn't do without. I went from using 400# of D.E. per month to 1- 25# bag (which is the equivalent of 200# D.E.) per month and had water that sparkled
View attachment 565695

Thanks for the response!

I didn't do anything special to remove oils, so I will take note that I'm going to have to service the filter sooner. My plan was to do a full clean and replacement of the cellulose every 6mo.s does that sound right or should I expect to do one in like 3 mo.s this first time around?

 

[1poolman1]

Thanks for the response!

I didn't do anything special to remove oils, so I will take note that I'm going to have to service the filter sooner. My plan was to do a full clean and replacement of the cellulose every 6mo.s does that sound right or should I expect to do one in like 3 mo.s this first time around?

You may have to do it much sooner than that if there are a lot of oils in the grids. You will find that a backwash of the cellulose will remove almost all from the filter, but "your mileage may vary." The first backwash won't remove much if there are oils involved. After that you may not need to do a teardown for a year, or whatever makes you comfortable, its your pool. I like to look at the grids every year to be sure there are no tears, holes, broken grids, etc.