9801ST00AMEN
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Figure 6. Air handler application recommendations when elbows are
used at appliance connection
Elbow with turning vanes from below
Square heel elbow from below
Round heel elbow from below
good
bad
bad
Elbow with turning vanes from the side
Square heel elbow from the side
Round heel elbow from the side
good bad bad
SECTION 4. COMBUSTION AIR SUPPLY AND FLUE SYSTEM
4.1
Flue systems must comply with national and local
regulations.
4.2
The products of combustion must be flued to outdoor
atmosphere. Common flues for more than one
appliance must
NOT
be used.
4.3 Combustion air should be taken from outdoor
atmosphere, this improves the operational efficiency of
the heating system.
4.4
Flues and combustion air ducts where connected to
the air heater must incorporate a disconnect section
adjacent to the appliance to facilitate removal of the
venter assembly for service and replacement
purposes. The flue system must therefore, be
supported independently.
Where flue systems are taken through elements of air
handling appliances then provision must be made to
allow servicing of the flue gas fan assembly. This will
entail fitting a special detachable transfer section from
the appliance flue and combustion air connection
sockets to the outside of the appliance. The main flue
should then respect the criteria outlined below.
4.5
Dimensions and allowances in suggested flueing and
combustion air intake arrangements are based upon
the use of smooth wall aluminium flue and combustion
air ducts and fittings equipped with positive sealing
gaskets.
