BoilerFaultCodesIntergas F01 Fault Code
The Intergas F01 fault code means: your boiler has detected a fault with its internal temperature sensor, meaning it cannot safely measure the heat of the water and has stopped working as a precaution.. It appears on 3 Intergas models in our database.
Technical description: S1 sensor short circuit
What causes the Intergas F01 fault?
This fault occurs when the boiler's control board loses its connection to the flow temperature sensor or receives an incorrect electrical signal. Most commonly, this is caused by the internal sensor failing due to age or the electrical wiring becoming damaged or loose. Because the boiler no longer knows how hot the water is, it shuts down to prevent the system from dangerously overheating.
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 F01 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Intergas F01 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