High
FLUE SENSOR on Johnson Starley Warmcair DW

Your boiler has detected a problem with the sensor that monitors the safety of the exhaust gases, and it has shut down to prevent overheating.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Flue temperature probe is damaged, disconnected, or the resistance does not relate to the actual flue temperature.

From this model's manual
Verified against the Johnson Starley Warmcair Dw installation & service manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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