BoilerFaultCodesTechnical 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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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