BoilerFaultCodesWhat the manual says
Manufacturer manualTemperature sensor error.
From this model's manual
Verified against the Warmhaus Enerwa installation & service manual, page 61.
What causes this fault?
This fault occurs when the boiler's internal computer loses communication with the temperature sensor, meaning it can no longer safely monitor how hot the water is. The most common reason is that the sensor has either worn out or suffered an electrical failure, but it can also be caused by loose or damaged wiring connecting the sensor to the main control board.
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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