BoilerFaultCodesTechnical description
Flue gas temperature is too high.
What causes this fault?
This fault occurs when the internal sensors detect that the waste gases leaving your boiler have reached an unsafely high temperature. The most common reasons are a significant build-up of limescale or debris inside the heat exchanger, or a lack of water flow preventing the heat from being transferred away from the unit effectively.
This issue is more common during winter when the boiler is running at maximum capacity for long periods to heat both the radiators and hot water simultaneously.
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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