Backwash leak


New member
Aug 31, 2018
About a week ago I noticed the water level dropping on my pool. Wasn't able to troubleshoot until this weekend due to work and constant rain. I'm seeing bubbles in both return lines. I checked with both skimmer and main drain, skimmer only and main drain only. Yesterday I backwashed and set my valve to skimmer only. When I started the pump I wash having trouble getting prime. I then set valve to skimmer and main drain and pump primed and seemed to be running fine. I woke up this morning and pool had leaked to below the skimmer. I checked the backwash line and water was leaking out of it. I changed the valve to main drain only and the leak slowed but was still leaking. I am thinking this is something with the multiport valve on the filter (Hayward Model S244T sand filter). Does anyone have any suggestions on this?

Texas Splash

Mod Squad
TFP Expert
LifeTime Supporter
It does sound like the MPV. Potential problem may be that unlike some MPVs, you may not be able to just change the spider gasket in yours. At least all the diagrams I'm checking like THIS ONE just shows the entire MPV and no spider gasket replacement part. So you may have to order the whole MPV. Someone else may chime in to confirm, but tomorrow I would double-check to make sure.