BoilerFaultCodesTechnical description
Debris in flue system; Debris in flue venturi. Appears if the boiler or flue system has developed a fault.
What causes this fault?
This fault occurs when the boiler's internal safety sensors detect that the airflow through the exhaust pipe is restricted or blocked. The most common cause is a build-up of dirt within a small component called the venturi, or a mechanical failure in the fan that prevents harmful waste gases from being pushed out of the property.
This fault can be more frequent during autumn and winter, as high winds can blow external debris into the flue or cause pressure shifts that trigger the safety sensor.
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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