Navien
Navien O-Ring EPDM P22 20029647A
EPDM O-ring, 21.8 x 2.4 mm, 70 Shore, black, for Navien NCB300 combi boilers.
£3.91
£3.26 ex. VAT · VAT at 20%
Same-day dispatch
Ordered by 4pm Mon–Fri, 10:30am Sat.
30-day returns
Unused, in original packaging.
What it is
An EPDM O-ring manufactured by Navien, measuring 21.8 mm inside diameter with a 2.4 mm cross-section and a 70 Shore hardness rating. It is supplied in black and carries the P22 designation. The ring seals a joint within the Navien NCB300 combi boiler range, preventing water loss at the connection it sits in.
Signs this part needs replacing
- Water weeping or a damp stain around the joint the ring seals
- The ring feels hard, brittle or has visible cracks when handled
- A flattened or deformed profile that no longer fills the groove
- Scale or mineral deposits built up on the ring surface
- Recurring pressure loss traced to the sealed connection
Before you order
- Confirm your boiler model against the fitment list above
- Check the existing ring dimensions and hardness match 21.8 x 2.4 mm, 70 Shore
- Inspect the sealing groove and mating face for scoring or corrosion before fitting a new ring
- Consider whether more than one ring on the same assembly needs replacing
No specification data held for this part.
| Make | Model / assembly | Reference | Years | Fitment |
|---|---|---|---|---|
| NAVIEN NCB300-28K COMBI - (Serial Number 3710) | — | — | — | |
| NAVIEN NCB300-28K COMBI - (Serial Number 3710) | — | — | — | |
| NAVIEN NCB300-37K COMBI - (Serial Number 3734) | — | — | — | |
| NAVIEN NCB300-37K COMBI - (Serial Number 3734) | — | — | — | |
| NAVIEN NCB300-41K COMBI - (Serial Number 3711) | — | — | — | |
| NAVIEN NCB300-41K COMBI - (Serial Number 3711) | — | — | — |
Documents & drawings
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