
Pentair Genuine OEM O-Ring, Square 8.5 in. Closure, 152509
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Quick overview
- Genuine Pentair OEM part 152509, the square section o-ring Pentair fits at the factory.
- Square cross section Made for the 8.5 in. closure groove; a round o-ring will not seat the same way.
- Challenger pumps The lid o-ring for Challenger high head and high flow models.
- Triton sand filters Also listed for the Triton II TR40 through TR140, the commercial TR100C and TR140C, and the Triton C-3.
- Stops air leaks A flattened or cracked lid o-ring lets air into the pump; a new one restores a full prime.
- Lube on install A light coat of silicone o-ring lubricant helps the seal seat and last.
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Genuine OEM O-Ring, Square 8.5 in. Closure, 152509
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Product details
Pentair part 152509 is the square section o-ring for the 8.5 in. closure on Challenger high head and high flow pumps. It is the genuine Pentair part, and it also appears in the parts lists for several Triton side mount sand filters: the Triton II TR40, TR50, TR60, TR100 and TR140, the commercial TR100C and TR140C, and the Triton C-3.
Why the profile matters
The closure groove is cut for a square cross section. Fitting a round o-ring of roughly the right diameter tends to end in a lid that will not seal, air in the pump basket and a pump that struggles to hold prime. Replacing the o-ring with the correct square section part is the fix.
Installing it
Clean the groove, wipe a light film of silicone o-ring lubricant onto the new o-ring and seat it before closing the lid. Avoid petroleum based lubricants, which attack the rubber.
| Brand | Pentair |
|---|---|
| Manufacturer part number | 152509 |
| UPC | 788379693503 |
| Part type | Pool pump part |
| Profile | Square section o-ring |
| Closure size | 8.5 in. |
| Fits | Pentair Challenger high head and high flow pumps; Triton II TR40, TR50, TR60, TR100, TR140; Triton II TR100C, TR140C; Triton C-3 side mount sand filters |
| Shipping weight | 0.02 lb |
| Ships | Parcel |
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Questions and answers
What people ask about this product, answered by our pool techs.
Which Pentair pumps use this o-ring?
It is listed for sand filters too. Is that right?
Why is the cross section square?
Should I lubricate it?
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