High
9A 361 on Worcester Bosch 26 CDi Xtra

Your boiler's internal computer parts do not recognise each other and are unable to communicate, preventing the heating from starting.

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 burner control unit that has been fitted is not compatible with the KIM (boiler identification module)

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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