BoilerFaultCodesWhat the manual says
Manufacturer manualInterruption: Return sensor - Return temperature sensor defective or not connected
Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
What causes this fault?
This fault occurs when the boiler's main control board loses its electrical connection to the sensor that monitors water coming back from your radiators. The most common reason is that the sensor itself has developed an internal electrical fault, or the thin wires connecting it to the system have become loose or damaged over time.
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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