High
6 flashes green on Main Insul 7

Your boiler's computer is experiencing an internal error, which has safely stopped the unit from running to prevent any unsafe conditions.

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

Miscellaneous: Internal fault in combustion control unit

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

E133View →

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