High
Section L on Alpha 240XE

Your boiler is not receiving a signal to turn on, which is likely due to the timer settings or the thermostat connections not communicating 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

Internal clock / external controls not calling for heat, or clock/wiring/PCB fault

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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