Pentair O-Ring for System 3 Filters | 35505-1425Z
- In stock, ready to ship
- Backordered: contact us for ETA
- SKU:
- 35505-1425Z
-
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About This Item
The Pentair O-Ring (35505-1425Z) is the OEM replacement O-ring for Pentair's System 3 filter line, including Modular Media, Sand, and D.E. filter models.
IMPORTANT: LUBRICATION REQUIRED — SOLD SEPARATELY
Always lubricate this O-ring with a silicone-based lubricant before installation. We carry the Pentair R172351 Lifeguard Silicone Lubricant — the OEM-matched product for Pentair equipment.
This O-ring seats at the filter tank/component interface on System 3 filter housings, maintaining a leak-free seal that keeps pressurized water contained during filtration and backwash cycles. A worn or cracked O-ring at this location is a common source of water seepage around the filter body.
Specifications
| Pentair Part Number | 35505-1425Z |
| Part Category | O-Rings |
| Quantity Included | Each |
Fits Into
| Brand | Equipment Line | Model / Part Number | Notes |
| Pentair | System 3 | S7M120 | |
| Pentair | System 3 | S7M400 | |
| Pentair | System 3 | S8M150 | |
| Pentair | System 3 | S8M500 | |
| Pentair | System 3 | S7S50 | |
| Pentair | System 3 | S8S70 | |
| Pentair | System 3 SD Series | S7D75 | |
| Pentair | System 3 SD Series | S8D110 | |
| Pentair | System 3 Modular D.E. | SMD | System 3 Modular D.E. Filters |
Compatibility is based on Pentair parts documentation and available OEM records. This is not an exhaustive list. For certainty, verify the part number in your equipment's manual or on the original part itself before ordering.
Poolaroo Pro Tip
Before installing, wipe the O-ring groove clean of old grease, sand, or D.E. residue — trapped debris at the seal surface is a leading cause of premature O-ring failure on System 3 filter housings. Apply a thin, even coat of Pentair R172351 Lifeguard Silicone Lubricant to the O-ring before seating it to ease assembly and extend service life.
