BoilerFaultCodesWorcester Bosch 9A361 Fault Code
The Worcester Bosch 9A361 fault code means: your boiler's internal computer parts are not communicating correctly because they appear to be mismatched or incompatible with each other.. It appears on 1 Worcester Bosch model in our database.
Technical description: The burner control unit that has been fitted is not compatible with the KIM (boiler identification module)
What causes the Worcester Bosch 9A361 fault?
This fault occurs when the boiler's main control board and its identity module are not 'speaking the same language' or are electrically mismatched. It usually happens after a repair where a technician has installed a replacement part that is the wrong version for your specific model, or if the internal data on one of the chips has become corrupted. Because these two brains must work in perfect harmony to ensure safe operation, the boiler shuts down until they are matched correctly.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Worcester Bosch models that show the 9A361 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Worcester Bosch 9A361 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