High Lockout
529 on Ideal Response SE

Your boiler has identified a problem with the fan motor, meaning it cannot safely clear waste gases and has shut down to prevent damage.

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 keeps turning / no tacho signal

What causes this fault?

This fault occurs when the boiler's control board tries to spin the fan but cannot confirm that it is actually moving or rotating at the correct speed. The most common reasons are a complete mechanical failure of the fan motor or a break in the delicate communication wires that send speed signals back to the main computer. Without this signal, the boiler cannot verify that it is safe to ignite and clear away harmful exhaust gases.

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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