BoilerFaultCodesTechnical description
Control mode: Return temperature sensor shorted out
What causes this fault?
This fault occurs when the sensor responsible for measuring the temperature of the water coming back from your radiators fails. The most common reason is an internal electrical failure within the sensor itself or moisture ingress that has damaged the connection, preventing the boiler from accurately monitoring the system's heat levels. Without this data, the boiler shuts down to prevent inaccurate firing and potential damage.
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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