High Lockout
C7216 on Worcester Bosch CDi Classic

Your boiler has stopped working because the fan that clears exhaust gases is not spinning at the correct speed.

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

Fan speed too low – check the fan harness and connector

What causes this fault?

This fault occurs when the boiler's control system detects that the fan is not spinning fast enough to safely clear waste gases from the flue. The most common reasons are a build-up of dirt within the fan housing, worn-out bearings that prevent the motor from turning freely, or a loose electrical connection between the fan and the main control board.

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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Related fault codes

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