BoilerFaultCodesWorcester Bosch C6216 Fault Code
The Worcester Bosch C6216 fault code means: your boiler has stopped working because the internal fan is spinning too slowly to safely clear away exhaust fumes.. It appears on 1 Worcester Bosch model in our database.
Technical description: The fan speed is too low
What causes the Worcester Bosch C6216 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Search the official register for a qualified engineer in your area.
Gas Safe Register →Worcester Bosch models that show the C6216 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Worcester Bosch C6216 fault code information on this page is sourced and cross-checked against the official Worcester Bosch service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026