High Lockout
C6216 on Worcester Bosch GB162

Your boiler has stopped working because the internal fan is spinning too slowly to safely clear away exhaust fumes.

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 too low

What causes this fault?

This fault occurs when the boiler's control system detects that the internal fan isn't reaching the necessary speed to safely vent exhaust gases outside. The most common reason is an electrical failure within the fan motor or a buildup of debris and carbon that physically restricts the fan from spinning freely.

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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