High Lockout
528 on Ideal Response SE

Your boiler has stopped working because the internal fan is not spinning correctly, meaning the system cannot safely clear away waste gases.

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

Air flow - Fan not running / no tacho signal

What causes this fault?

This fault occurs when the boiler's control system detects that the fan is not spinning at the required speed to safely vent exhaust gases. The most common reasons are a complete mechanical failure of the fan motor, a loose connection in the wiring, or a fault on the main circuit board that prevents it from sending power to the fan.

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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