High
FE95 on Alpha FMK

Your boiler has detected that an external temperature sensor is sending an incorrect or impossible reading, which is preventing the system from operating correctly.

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

External flow sensor out of range or short circuit/External flow sensor measures a temperature outside of normal workingrange.

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

FE94View →

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