BoilerFaultCodesYour boiler has stopped working because it cannot correctly monitor the temperature of the water flowing through the system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flow sensor: Sensor failed open or closed circuit
What causes this fault?
This fault occurs when the boiler's internal computer loses communication with the sensor that monitors the heat of the water leaving the unit. The most common reason is that the sensor has physically failed due to age or heat stress, but it can also be caused by a loose connection or damaged wiring. Because the boiler no longer knows how hot the water is, it shuts down as a safety precaution 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 5 — no call-out fees, no surprises.
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