BoilerFaultCodesWhat the manual says
Manufacturer manualSensor fault S2
From this model's manual
Verified against the Intergas Combi Compact Hre 24 18 installation & service manual, page 41.
What causes this fault?
This fault occurs when the boiler's internal computer stops receiving a reliable temperature reading from the sensor on the return pipe. It is usually caused by the sensor itself failing, or a loose connection in the wiring that prevents the signal from reaching the control board. For safety, the boiler shuts down because it can no longer monitor if the water returning from your radiators is at a safe temperature.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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