BoilerFaultCodesTechnical description
Short circuit on return sensor
What causes this fault?
This fault occurs when the internal control board receives an electrical signal from the return sensor that is outside its normal operating range. The most common reason is that the sensor's internal wiring has failed or a physical break in the connection has occurred, preventing the boiler from accurately monitoring the temperature of the water coming back from your radiators.
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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