DE filter question/help

Grrltraveler2007 · Oct 31, 2020

I cleaned my filter today and rinsed the grids. I checked the grids and could only see one that might have the tiniest of tears on it, so I replaced it.
When I started it back up, I started to put the DE in it and it started coming out into the pool. I took everything apart and we checked it again, put it back together, all looking fine.
Turned back on and again with the filter coming out into the pool

Is there anything other than microscopic tears that I obviously missed that would keep the DE from coating the grids? I can only think that I can't see the tears at all.

Every time I take this thing apart, I lose a grid or two to tears along the spine and have to replace - its old but been such a great filter just wondering if I am missing something.

Help.

Pentair 4000 Series - must be original to pool in 1980s.

Also I have never loved cleaning the DE filter but didn't necessary want to replace it before now. If you were going to get a new filter, do you recommend another DE filter or would a cartridge filter work as well for my pool?

HermanTX · Oct 31, 2020

Some DE could come out initially but it should stop. Did you ensure your o-ring seal on the up-pipe was lubed? Also, did you check your plastic manifold on top. Some have found cracks in that - in fact very small cracks. Also, does yours have that small screen on top of the manifold? Check that for holes or loose fitting.

If you do want to buy a new filter, many suggest a cartridge, just ensure that it can fit in your space because you should get a large sq ft area cartridge filter for your 21k gals. I could not fit a cartridge filter in my space unless I rerouted a lot of pipes so I just did another DE. I like DE so was not bothered.

Oly · Oct 31, 2020

If your DE grids are tearing easily then you should replace them all as a set. Check the items listed in Herman TX's post above.

Grrltraveler2007 · Oct 31, 2020

Thanks for the answers. Will check again in the morning as its gone too hot out there.

Grrltraveler2007 · Oct 31, 2020

Upon review of your notes, my filter has never had an O ring on the up-pipe. I looked at a manual for the Pentair 4000 and I can see where you got that.

Mine appears to be older than that, Purex Pentair and looks more like this one, although this one is only a 2000: Purex SM and SMBW 2000 Series Filters | My Pool

I can't actually find a manual or picture of mine, its that old. lol

I will take apart and check the manifolds and the grids again.

Rancho Cost-a-Lotta · Oct 31, 2020

Make sure the "vent tube screen cap" is not damaged and is securely on the vent tube. On this site, I've seen the smallest of cracks on manifolds that have caused DE to return to the pool.

HermanTX · Oct 31, 2020

Grrltraveler2007 said:
Upon review of your notes, my filter has never had an O ring on the up-pipe. I looked at a manual for the Pentair 4000 and I can see where you got that.

Mine appears to be older than that, Purex Pentair and looks more like this one, although this one is only a 2000: Purex SM and SMBW 2000 Series Filters | My Pool

I can't actually find a manual or picture of mine, its that old. lol

I will take apart and check the manifolds and the grids again.

Thanks for update. I should have mentioned that I did try to search for your model but unsuccessful so some of my feedback was based on Pentair filters we have seen on this site and their issues. Let us know what you find. It may be best to transition to a new filter (you could have further issues with the shell in the future if the filter is 30+ years old). A cartridge filter is a good choice if you can fit it on your equipment pad without much issue. Keep us updated.