BoilerFaultCodesYour boiler has stopped working because it cannot communicate with the sensor that monitors the temperature of the water returning to the unit.
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 main control board loses the electrical signal from the sensor that monitors the temperature of the water returning from your radiators. The most common reason is a physical failure of the sensor itself, but it can also be caused by loose or damaged internal wiring that prevents the signal from reaching the computer.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like F.01 / F.1 — no call-out fees, no surprises.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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