BoilerFaultCodesYour boiler has lost connection with the sensor that monitors the water returning to the unit, causing it to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Return temperature sensor interruption
What causes this fault?
This fault occurs when the boiler's control board can no longer read the temperature of the water coming back from your radiators. This is usually caused by the internal sensor failing due to age, or a loose connection in the wiring that prevents the signal from reaching the main computer.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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