Navien
Navien O-Ring EPDM 20003022A
Black EPDM O-ring, 18.8 x 2.6 mm, 70 hardness, part 20003022A, 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
The Navien O-Ring EPDM 18.8 x 2.6, 70, BK is a black EPDM sealing ring supplied under part number 20003022A. It is used to seal a joint within Navien NCB300 combi boilers, preventing water weeping at the connection it sits in.
Signs this part needs replacing
- Visible weeping or a damp trace around the joint the ring seals
- The ring feels hard, brittle or has lost its elasticity
- Cracks, nicks or a flattened cross-section on the ring
- Black residue, scale or debris trapped on the sealing face
- System pressure dropping with no other obvious cause
Before you order
- Confirm your boiler model against the fitment list above
- Check the dimensions and material of the old ring before ordering
- Inspect the sealing face and joint for damage, scale or debris
- Consider whether other seals in the same joint should be renewed at the same time
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
Everything we hold for this part. Where a document exists but we don't hold it, the technical team will source it from the manufacturer — usually the same working day.
No technical questions yet for this part.
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