BoilerFaultCodesYour boiler has stopped working because a internal sensor that monitors the temperature of the water returning to the unit has developed an electrical fault.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Short circuit: Return sensor - Return temperature sensor defective or has short-circuited
What causes this fault?
This fault occurs when the boiler's control board detects an incorrect electrical signal from the sensor that monitors water temperature coming back from your radiators. The most common reason is that the sensor's internal components have failed or the wiring connecting it to the main board has become damaged or loose. Because the boiler can no longer safely track how hot the water is, it shuts down to prevent overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like F.11 — no call-out fees, no surprises.
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