Baxi
Myson and Sit 402989 oxypilot
Sit oxypilot assembly, part 402989, a complete pilot unit (injector, thermocouple, electrode, bracket) used on Myson Housewarmer 45 and 55 back boilers.
At a glance
- Fitting must be carried out by a Gas Safe registered engineer
£54.00
£45.00 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 402989 is a Sit oxypilot assembly used on Myson Housewarmer back boilers. It is a complete pilot assembly - injector, thermocouple, electrode and bracket - that lights and holds a stable pilot flame ready to ignite the main burner.
Signs this part needs replacing
- Pilot won't light or won't stay lit
- Pilot flame is weak, yellow, or lifts away from the thermocouple
- Boiler locks out on "no flame" faults
- Visible corrosion or damage to the injector or electrode
Before you order
- Confirm the part number on your existing pilot assembly matches 402989 before ordering
- Isolate gas and electrical power before removal
- Fitting must be carried out by a Gas Safe registered engineer
- As this part is discontinued, check stock and warranty before committing
No specification data held for this part.
No fitment data held for this part.
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 documents held for this part. The technical team will source them from the manufacturer — usually the same working day.
No technical questions yet for this part.
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