The Pentair 192323 is the genuine OEM o-ring listed as the stand pipe o-ring, and also as the stand pipe or strainer pot to pump body gasket on Volute Hydropump models.
Where it appears
Pentair carries this ring across several parts lists. It shows up in the PacFab FNS fiberglass DE filter parts for the FNS24, FNS36, FNS48 and FNS60, in the Nautilus and Nautilus Plus DE filter parts, and on the pump side under the PacFab Hydropump 590 and 700 series and the Sea Horse cartridge filter ranges. Check your own parts diagram against the position you are working on.
Why it is worth doing
O-rings are the cheapest thing in the system and the most common cause of a leak or an air draw. Rubber hardens, takes a permanent set in the groove and stops recovering when the joint is opened. A ring that looks fine can still be the reason the pump will not hold prime.
Fitting
Clean the groove and the mating face, then use a silicone o-ring lubricant on the ring before assembly. It seats more evenly, and it does not weld itself to the housing before the next service.
