BoilerFaultCodesYour boiler's internal thermometer that measures the temperature of the water leaving the unit has stopped working correctly, which means the system cannot safely regulate heat.
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 fault – possible causes: sensor damaged, short circuited or wiring broken check the wiring
What causes this fault?
This fault occurs when the boiler's control board loses communication with the temperature sensor on the main pipe. The most common reason is that the sensor's internal electrical resistance has failed due to age, or the thin wires connecting it to the main computer have become loose or corroded. 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 F10 — no call-out fees, no surprises.
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Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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