Onga Pool Filter

[robert]

I had a new Onga Sand filter installed and despite changing the sand and having less of it in the filter, we are still getting sand discharged back into the pool when on back wash. When the filter is set to filter we lose sand as well as enormous amounts of water through the overflow. Since lowering the amount of sand in the filter we don't lose nearly as much sand as before but we continue to lose too much water through the overflow. We are using a 1hp pump. I am now wondering if the pressure of the pump is more than the sand filter can cope with???
I'd be grateful to receive any suggestions. Thank you.

[dynamictiger]

I think from your description the multi-port valve is on the filter incorrectly or the plate has been turned 180 degrees from where it should be. A higher pressure would seal the change plate tighter not cause it to discharge to the pool on backwash. Normally the valve has an indicator of some sort as to where the top plate should line up with the body. Often this is a screw that is different somehow than the others.

Is this a pantera filter?