High
E23 on Ravenheat TS 100

Your boiler has detected an issue with the sensor that monitors exhaust gases, and it has shut down for safety purposes.

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

Flue sensor damaged

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

E05View →E24View →E25View →

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