BoilerFaultCodesTechnical description
Fault in flue system
What causes this fault?
This fault occurs when the boiler's internal safety sensors detect that the flue system is obstructed or unable to clear exhaust fumes effectively. The most common reason is a blockage or restriction in the flue pipe itself, or a mechanical failure in the fan that is responsible for pushing gases out of your home.
This fault is more common during periods of high winds, which can cause pressure imbalances in the flue, or during freezing temperatures if ice builds up around the flue terminal.
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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