Navien
Navien 3-Way Valve 30031262A
Navien 3-way diverter valve, part 30031262A, for NCB300 and NCB500 combi boilers.
At a glance
- Part type: 3-way valve (diverter valve)
£45.31
£37.76 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 3-Way Valve, part number 30031262A, is a diverter valve used in Navien NCB300 and NCB500 combi boilers. It directs the flow of heated water between the domestic hot water circuit and the central heating circuit. It is a serviceable component within the boiler's hydraulic assembly.
Signs this part needs replacing
- No hot water while the heating is running, or heating that continues during a hot water draw
- Radiators warming when only hot water is called for
- The valve actuator fails to move or gives no response when the boiler changes mode
- Water weeping from the valve body or its connections
- Boiler lockout or fault codes linked to the diverter valve
Before you order
- Confirm your boiler model and serial number against the fitment list above
- Check the part number on the existing valve matches 30031262A
- Establish whether the fault lies with the valve body or the actuator before ordering
- Isolate the boiler and drain down before fitting
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) | — | — | — | |
| NAVIEN NCB500-1S+/32K COMBI - (Serial Number 3924) | — | — | — | |
| NAVIEN NCB500-1S+/32K COMBI - (Serial Number 3924) | — | — | — | |
| NAVIEN NCB500-2S+/41K COMBI - (Serial Number 3712) | — | — | — | |
| NAVIEN NCB500-2S+/41K COMBI - (Serial Number 3712) | — | — | — |
Showing 10 of 12 compatible appliances.
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.
NAVIEN appliance manual — NCB300-28K COMBI - (Serial Number 3710), NCB300-37K COMBI - (Serial Number 3734), NCB300-41K COMBI - (Serial Number 3711)
manualmanualNAVIEN appliance manual — NCB500-1S+/32K COMBI - (Serial Number 3924), NCB500-2S+/41K COMBI - (Serial Number 3712), NCB500-2S/37K COMBI - (Serial Number 3735)
manualNo technical questions yet for this part.
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