High
E2 on Firebird Enviro System

Your boiler has detected a problem with the sensor that monitors exhaust gas temperatures, causing the system to shut down for safety.

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 thermistor fault (if flue thermistor installed into flue).

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

E1View →E3View →

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