High
49 on Alpha E-Tec

Your boiler is shutting itself down because the water returning from your radiators is getting far too hot, which suggests an issue with water flow or a faulty sensor.

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

Return sensor has detected a high temperature (90°) on the heat exchanger return circuit

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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