High
ER 11 + RESET on Johnson Starley Warmcair DW

Your boiler thinks it sees a flame even though it hasn't started yet, which is a safety conflict that prevents it from turning on.

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

False flame (detection electrode fault)

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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