BoilerFaultCodesYour boiler's internal thermometer that measures water temperature is faulty or has a wiring issue, preventing the system from heating up safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Delivery sensor error, sensor damaged wiring shorted or disconnected
What causes this fault?
This fault occurs when the boiler's control board loses communication with the sensor that monitors the temperature of the water leaving the unit. The most common reason is that the internal component has suffered an electrical failure or the connection wires have become loose or damaged over time. 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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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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