BoilerFaultCodesYour boiler has detected a fault with the sensor that monitors water returning from your radiators, preventing the system from heating up safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Return sensor short circuit
What causes this fault?
This fault occurs when the sensor responsible for measuring the temperature of the water returning to the boiler develops an electrical shortcut. The most common reason is that the internal component of the sensor has failed or the protective insulation on the connecting wires has worn away, causing a constant, incorrect electrical signal.
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 F10 — 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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