High Lockout
C7217 on Worcester Bosch GB162

Your boiler's fan is failing to spin at the correct speed to begin the ignition process, preventing the boiler from firing up.

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

The fan speed is irregular when starting up

What causes this fault?

This fault occurs when the boiler's internal computer detects that the fan is not rotating fast enough to safely clear out the combustion chamber before ignition. The most common reason is a mechanical failure within the fan motor or a buildup of debris, though electronic issues with the control board can also stop the fan from receiving the correct power signals.

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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