BoilerFaultCodesWorcester Bosch E9210 Fault Code
The Worcester Bosch E9210 fault code means: your boiler has shut down because it is detecting dangerously high temperatures in the exhaust flue or a fault with the safety sensor itself.. It appears on 1 Worcester Bosch model in our database.
Technical description: The temperature measured by the flue gas sensor is too high and is open
What causes the Worcester Bosch E9210 fault?
This fault occurs when the internal safety sensors detect that the exhaust gases are becoming hot enough to potentially damage the boiler's components. The most common reason is a buildup of debris or combustion by-products inside the heat exchanger, which prevents heat from being transferred to your radiators and instead pushes it out through the flue. It can also be triggered by a physical failure or loose connection within the temperature sensor itself.
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 E9210 fault code
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Source
Worcester Bosch E9210 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