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Overview of the concentric flue system
The concentric flue system provides the appliance with combustion air and removes the
flue gases from the appliance. The concentric flue system is made of these items:
Item
Description
Concentric flue
The concentric flue is a pipe with an inner pipe. The
inner pipe is used as flue gas channel and the space
between the inner pipe and the outer pipe is used as
combustion air channel
Flue gas channel
The flue gases from the appliance flow through the
channel to the outlet by natural draught or, with the
Opti-Vent installed, forced draught.
Combustion air channel
Supplies the appliance with fresh air from the outlet
through the channel
Outlet/terminal
Entry for the combustion air channel and exit for the
flue gas channel
Overview of the concentric flue system
Gas Fire Front 90-60
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