BoilerFaultCodesWhat the manual says
Manufacturer manualSensor fault S1
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 main flow sensor, which monitors the temperature of the water leaving the heat exchanger, fails to provide a consistent or logical reading. The most common reason is that the internal electrical component of the sensor has worn out or developed a short circuit, preventing the control board from knowing if the water 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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