BoilerFaultCodesYour boiler has stopped working because it cannot accurately measure its own internal temperature due to a broken or disconnected sensor wire.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Burner blocked - Boiler temperature sensor lead break
What causes this fault?
This fault occurs when the boiler's main internal thermometer stops sending a steady electrical signal to the control board. The most common reason is a physical break in the thin copper wiring or a connector that has vibrated loose, preventing the boiler from knowing its own temperature. Because the boiler cannot safely monitor if it is overheating, it shuts down the burner as a safety precaution.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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