High
0E98 on Alpha FMK

Your boiler has detected that its temperature sensors are giving conflicting or incorrect readings, 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

Flow and return sensor anomaly detected (sensor shows incorrect temperature value)

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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