BoilerFaultCodesYour boiler has stopped working because a sensor that monitors the temperature of the water returning to the unit has detected 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: Return NTC short circuit
What causes this fault?
This fault occurs when the boiler's internal computer receives an incorrect electrical signal from the sensor that monitors cooled water returning from your radiators. The most common reason is that the sensor has developed an internal electrical short, or the wiring connecting it to the main control board has become damaged or loose.
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.11 — no call-out fees, no surprises.
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