BoilerFaultCodesYour boiler has detected that the exhaust gases are getting too hot or there is a fault with the temperature sensor, causing the system 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: Flue sensor short circuit / Flue temperature too high
What causes this fault?
This fault occurs when the boiler's safety system detects that the gases leaving through the flue are significantly hotter than they should be, or the sensor itself has malfunctioned. The most common reasons are a build-up of debris inside the heat exchanger that prevents efficient cooling, or a simple electrical failure in the flue sensor's wiring.
This issue is more common during the winter months when the boiler is running at maximum capacity for long periods to heat the radiators.
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 F07 — 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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