High
ER 05 + RESET on Johnson Starley Warmcair DW

Your boiler has stopped working because the internal fan used for safe combustion is not spinning or cannot be detected by the system control board.

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 tacho from 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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