BoilerFaultCodesIntergas FO30 Fault Code
The Intergas FO30 fault code means: your boiler has stopped working because it cannot detect any water flowing through the system, meaning it cannot safely heat your home or water.. It appears on 1 Intergas model in our database.
Technical description: Sensor S3 fault
What causes the Intergas FO30 fault?
This fault occurs when the boiler's internal flow sensor fails to detect water movement when the pump is running. The most common reasons are a mechanical failure of the sensor itself, a blockage preventing water circulation, or a communication issue between the sensor and the main control board.
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 FO30 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Intergas FO30 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