High
31 on Johnson Starley C10d

Your boiler has lost connection with its internal air temperature sensor, which means it cannot safely monitor the heat level and has stopped working.

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 open circuit. Temperature sensor not connected or failed. Check wiring connections. Check sensor continuity.

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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