BoilerFaultCodesTechnical description
Flue obstruction
What causes this fault?
This fault occurs when the boiler detects that air isn't moving through the system correctly, usually because something is physically blocking the flue pipe or the internal air pathways. It is often caused by debris like leaves or a bird's nest in the external pipe, or a failing internal fan that can no longer push the exhaust gases out of your home safely.
This fault can be more common in autumn and winter, as high winds can blow debris into the flue or nesting animals may seek warmth inside the pipework.
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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