BoilerFaultCodesTechnical description
Flue sensor out of range. Flue sensor measures a temperature outside normal working range.
What causes this fault?
This fault occurs when the internal sensor responsible for monitoring exhaust temperature signals a reading that is physically impossible or dangerously high. The most common reason is a failing sensor sending incorrect data, but it can also be triggered by a build-up of debris or scale within the heat exchanger causing the system to overheat.
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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