High
30 on Johnson Starley C16d

Your boiler has stopped working because it has detected an electrical fault with the internal sensor that monitors air temperature.

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. Check wiring and connections for shorting to earth. Check sensor resistance.

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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