I have a DE filter that I have had acid washed every year. when I first put it in the start of the season it goes for about 4 weeks before I have to backwash due to pressure rising. Then every two weeks for about 3 cycles and then 1 week and now the pressure is rising before 1 week is up. I replaced the multiport valve at the end of 2021 and thats the only thing I can thing of that is causing this as it has happened the last 2 seasons. Maybe its not backwashing well enough. I have inquired with multiple pool people and no one knows why this is happening. Have even opened up the de filter midway thru the season and its not dirty. its a mystery? Someone said to bump the filter but this DE filter doesnt have a bump handle so not sure if it is possible to do and if so how? I dont have an algae issue and keep the pool highly chlorinated and have a nature 2 cartridge. My guess is that the de is not really cleaning off the grids well when back washing but I never had this issue before last year. any help would.be appreciated.
Pressure in Jandy DE filter rising fast btw backwashing
- Thread starter Poolhappy2009
- Start date
Tell us your backwash process. How long do you leave it in backwash state? How long do you leave it in rinse position?
How many times do you do this cycle of backwash, rinse?
You could have “unseen algae” as something is clogging your grids. What type of DE do you use?
How many times do you do this cycle of backwash, rinse?
You could have “unseen algae” as something is clogging your grids. What type of DE do you use?
Hello ...I back wash until the glass is clear..maybe 60 secs...then I rinse for about 20 to 30 seconds and repeat this process 5 times before putting the multiport back in filter mode. I have been using the same process for 14 seasons and same type of DE and only started experiencing this last season and this season despite the grids being acid washed professionally every year...most recently early April before pool was opened this year. I have a nature 2 cartridge and I use an algaecide every month so if I have algae it certainly is unseen because there is no visible sign of it and when my water gets tested they dont show any sign of algae either. brand of DE from pool store is BIG SPLASH...bags are 6 lbs. any help is much appreciated. thanks
Replace your grids and don't use acid to clean them. If not removed first, any oil on the fabric will become a coating that can't be removed that clogs the grid. There is always oil in the filter. The only time an acid cleaning is needed is if there is calcium that may be coating the grid, and that seldom happens unless the water chemistry is very bad.
thanks.....I bring my grids to pool store every year to be cleaned. I am.assuming they clean them with acid and water solution. why do they need to be replaced...I'm not quite following with the oil explanation...why is there always oil on the filter? from suntan lotion when people get in the pool?
There are oils in the water from people, you perspire even in the water and that also brings body oil with it. Suntan oils, yes. Vegetation (leaves, grasses, etc.) that may get into the pool produce oils. The oils are there. If not removed first from a filter, cartridge or DE, acid will cause it to form into a coating that can not be removed. That section of cartridge or grid is no longer porous, water can not get through it so it won't filter anything and has lessened the effective area of the filter.
Please note the instructions at this site by a filter media manufacturer. Though it is for a cartridge filter, it is the same for a DE grid.
Note point 6 in the second question. Having had to replace many grids and cartridges for customers who didn't know or follow these instructions and who were told to "just acid wash them," I found it to be true. They all had the same complaint that you have, short filter cycles after an acid wash.
Okay. thanks for explanation. one last question...then how should you clean your.grids each season to remove the oils?