High
30 on Johnson Starley C26d

Your boiler has stopped working because it thinks the air in the heating ducts is overheating due to a faulty electrical sensor.

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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