DE filter backwash (newbie)

[Phillbo]

My post backwash pressure is 12psi. I backwash when it climbs to 20psi.

Given the fact your post backwash pressure is 18psi, you may want to consider opening it up and cleaning the grids. You really have no way of knowing the last time that was done so might as well start from scratch.

[hikernut]

Thanks for the feedback... really appreciate it.

Yes, the pressure gauge reads zero when off, and goes to same value each time it's turned on, so it seems the gauge is okay.

I did a bit of brushing the two days before backwashing, which was some combination of sand and/or algae, and I definitely saw that coming out of the backwash hose.

I'll take the filter apart and take a look in the near future...

hikernut

[Gretzky99]

My brand new filter the 3620 started at 18 when i turned it on (pool was green at the time)..it always returns to that level..i backwash at 28-30.
i thought it should be the starting pressure should be from 8 to 10 ..but i guess not
I've had to back wash every 2 hours except for sleep time since and the pool is almost ready now.

[Watermom]

I am not familiar with what normal pressure should be on a DE filter since I use a sand filter on my pool, but I can tell you that algae clogs a DE filter fast. Hopefully someone else will chime in who can tell you more about what normal pressure should be.

[Gretzky99]

Couldn't clog a brand new filter within a minute..but it seems to be working fine anyway

[vinper]

I open mine up and clean grids after every 2 backwash and recharge cycles . not that hard . see what pressure reading you get on rinse cycle . you could have backpressure by a blockage or partially closed valve

[Gretzky99]

ok thanks..i have another question..
when do i open the valve on the top to let air out? (other than opening it up to clean it)