If you're having air mysteriously leaking into you suction system, it could be a bad seal in your Jandy Valve. You can easily replace the internal components to prevent cutting out the entire valve, as long as the valve housing isn't
cracked or warped. I opted to replace the diverter while I had the whole thing open. This diverter fit into the old valve housing well and makes a water tight seal after the housing cover is put in place (mine didn't make a seal until I put the cover on). Also included the two rubber o-rings and the plastic o-ring spacer that goes in between them, so no need to buy those.