BoilerFaultCodesTechnical description
Central heating return sensor error, possibly damaged
What causes this fault?
This fault occurs when the internal control board loses communication with the sensor that measures the temperature of water coming back from your radiators. The most common reason is that the sensor has physically failed due to age, or the electrical wiring connecting it to the main board has become loose or damaged.
This issue often becomes apparent in autumn when the heating is turned on for the first time after summer, as the sensor fails to respond to the sudden change in water 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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