Installation manual

6
DUCTING
Ducting work should be fabricated by the installing contractor in
accordance with local codes. Industry manuals may be used as a
guide when sizing and designing the duct system, such as
NESCA (National Environmental Systems Contractors
Association, 1501 Wilson Blvd., Arlington, Virginia 22209).
The unit should be placed as close as possible to the space to be
air conditioned allowing clearance dimensions as indicated.
Ducts should run as directly as possible to supply and return
outlets. Use of nonflammable weatherproof flexible connectors
on both supply and return connections at the unit to reduce noise
transmission is recommended.
It is preferable to install the unit on the roof of the structure if the
registers or diffusers are located in the wall or ceiling. A slab
installation is recommended when the registers are low on the
wall or in the floor.
Connecting the Return and Supply Flexible Duct in
Manufactured or Modular Housing Application
The return and supply fittings are to be attached at the unit to a
suitable square-to-round duct converter. Your distributor has a
factory-designed square-to-round converter transition. The
model numbers of these kits are as follows: Small Chassis 25"
SQRPCH101, Medium Chassis 27.5" SQRPCH102, Large and
Extra Large Chassis 32.5" and 36" SQRPCH103. See
Specification Sheets for dimension details. The SQRPCH101 has
14" (35.6 cm) duct collar on supply and 16" (40.6 cm) duct collar
(equivalent diameter, opening is oval) on the return.
The SQRPCH102 and SQRPCH103 have 14" (35.6 cm) duct
collar on supply and 18" (45.7 cm) duct collar (equivalent
diameter, opening is oval) on the return. The collars are to be
slipped into the openings, and the flanges bent around the
converter. The square-to-round converter is attached to the
flanges of the square duct openings.
The flexible duct is then clamped on to the collars. Once the duct
is affixed to the unit, seal the collars and flanges with a proper
waterproof sealant.
It is strongly encouraged to use appropriately-sized ducts based
upon the CFM for your application (unit’s CFM). If duct sizing
through industry manuals or air duct calculators require larger
ducts than converter openings, run larger duct size up to unit
converter openings and reduce with a reducer duct fitting or
transition right at the unit.
Square-to-Round Duct Converter Panel
Plenum Application
A suitable plenum or square duct must be constructed. The duct
cross-sectional area should be determined by industry duct
sizing manuals or air duct calculators.
On ductwork exposed to outside air conditions of temperature
and humidity, use an insulation with a good K factor, and a vapor
barrier. Industry practices should be followed. Balancing
dampers are recommended for each branch duct in the supply
system. Ductwork should be properly supported from the unit.
NOTE: Proper sealing of all duct work and air handling
compartments is extremely important to overall unit efficiency.
Goodman 98
Connecting unit ductwork to unauthorized heat producing
devices such as a fireplace insert, stove, etc., may result
in property damage, fire, carbon monoxide poisoning,
explosion, personal injury or death.
WARNING
A. Outer flange
B. Square to round duct converter panel
C. Bead
D. Starter flange
B
C
D
A