BoilerFaultCodesYour boiler has lost its connection to the sensor that monitors the temperature of the water leaving the unit, usually causing the system to stop working for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flow temperature sensor interruption
What causes this fault?
This fault occurs when the boiler's central control board can no longer detect an electrical signal from the sensor that monitors internal water temperature. The most common reason is that the sensor itself has failed internally, though it can also be caused by a loose connection or damaged wiring between the sensor and the main circuit board.
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.00 — no call-out fees, no surprises.
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