Johnson & Starley
Johnson & Starley 1in gas valve, millivolt, natural gas S00851
Genuine Johnson & Starley 1in millivolt gas valve (S00851) for State SBT100-400 boilers, controlling gas flow to the main burner without mains electricity.
At a glance
- Also known as 1691829
- Gas Safe registered engineer required to isolate gas and refit
£1,041.85
£868.21 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
A millivolt-controlled gas valve for Johnson & Starley State SBT100-400 boilers running on natural gas. It uses the millivolt signal from the thermocouple/thermopile to control gas flow to the main burner without needing mains electricity.
Signs this part needs replacing
- Main burner won't light even though the pilot is lit
- Gas valve fails to hold open, or the burner cuts out shortly after firing
- Boiler locks out on ignition or flame failure faults
- Valve is stiff, seized or visibly leaking gas
Before you order
- Confirm your boiler is the millivolt, non-electronic version before ordering
- Match the 1in connection size and part number on your existing valve
- Gas Safe registered engineer required to isolate gas and refit
Compliance
| Alternative numbers | 1691829 |
|---|
No fitment data held for this part.
Documents & drawings
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No documents held for this part. The technical team will source them from the manufacturer — usually the same working day.
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