BoilerFaultCodesYour boiler has detected that the water temperature is getting too hot while you are trying to use your taps or shower, causing it to shut down 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: Temperature too high during DHW demand.
What causes this fault?
This fault occurs when the water temperature within the boiler climbs too quickly or exceeds safe limits while you are using your hot water. It is usually caused by a blockage or a component failure that prevents heat from being transferred away from the burner and into your taps effectively. Common culprits include a faulty temperature sensor giving incorrect readings or a stuck diverter valve that isn't directing the hot water where it needs to go.
This fault can be more noticeable in summer when the incoming mains water is naturally warmer, giving the boiler less 'room' to manage high temperatures before hitting a safety limit.
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 F002 — 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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