High
E04 on Johnson Starley C26d

Your boiler has stopped working because it cannot detect that the combustion fan is spinning properly to safely vent waste gases.

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

No fan speed signal (Combustion fan)

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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Related fault codes

E01View →E05View →

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