High
30 on Johnson Starley C16u

Your boiler has detected a fault with the sensor that monitors air temperature within the ducting, causing it to stop running for safety.

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.

Technical description

Duct air temperature sensor short circuit. Temperature sensor shorted to earth or failed

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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