For some reason, when I bleed air from my filter.. if the filter is not bypassed I get DE in the pool. This is my second DE filter in a month. The first one did the same thing (long story short, they installed the wrong filter). I am positive there was no damage to the grids or manifold in the first one, and definitely not in this one (I examined everything before starting it up).
Today I went to clean the pump basket, so I turned off the pump, turned the multiport to closed to prevent this DE backflow phenomenon from happening, and opened the lid to clean basket. Everything was fine, but when I put the lid back on and went to prime the pump, about a second later I realized I forgot to turn the multiport back to filter, so a bit of pressure got up in there before I stopped the pump. This made it very very difficult to push the spring open on the multiport valve.. so I bled air out of the filter hoping that would help.. which I think it did. I still had to bang on the handle a bit to finally get it to open, and when it did I heard lots of gurgling for a few seconds. I don't think the multiport is hosed (hopefully, and I think from now on I'm going to just set it to recirculate while I'm cleaning the pump basket or the filter). I have a Jandy check valve between the pump and the filter, and so nothing should have been able to get back into the pump from the filter, but somehow a huge cloud of DE came up from the main drain. I have no idea how this is even possible with the check valve, and I didn't even see any DE going back through the pump. Everything seems to be working fine again now but this whole DE in the pool thing is baffling to me as it takes a long time for it to get cleaned out.
My previous filter had a push/pull valve so I didn't have a choice when bleeding air but to leave it alone. Every time I did it, DE would fill the pump and eventually start coming out of my drains and skimmers. At the time I had a liquidator installed, and it was installed poorly. I thought that it was allowing some air into the system and causing the backflow. But when I got the new filter installed, they took out the liquidator (long story short, needed to eliminate it for troubleshooting purposes) and replaced the push pull with a multiport , plus I installed a flovis meter/check valve and it's still happening. If I don't close off the multiport, DE is getting into the pool when I bleed air. It doesn't happen unless I open the air relief valve.
Even when the system is running normal and I turn the air relief valve, the water that comes out is very filled with DE (is that normal?)
I know I put exactly 6 lbs of it in when I started it up but I guess it seems like there is a lot of extra DE in there.. either that or something else is wrong. Is this all normal operation or do I need to investigate a leak somewhere?