BoilerFaultCodesIntergas F12 Fault Code
The Intergas F12 fault code means: your boiler has stopped providing hot water because the internal sensor that monitors water temperature has developed an electrical fault.. It appears on 3 Intergas models in our database.
Technical description: DHW sensor short circuit
What causes the Intergas F12 fault?
This fault occurs when the electrical connection within the hot water temperature sensor fails or is damaged, often due to internal wear or moisture ingress. When this happens, the boiler's control board can no longer read the water temperature accurately and shuts down the burner as a safety precaution. The most common cause is a failed internal component within the sensor itself or a wire that has become trapped or frayed.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Gas Safe Register →Intergas models that show the F12 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Intergas F12 fault code information on this page is sourced and cross-checked against the official Intergas service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026