High
E23 on Ariston Bravo 24 MFFI

Your boiler has detected that the internal exhaust fan is not spinning fast enough to remove combustion gases safely, so it has shut down to prevent a hazard.

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

Low fan speed

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

E25View →

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