Installation Manual

7
RIGGING DETAILS
IMPORTANT: If using bottom discharge with roof curb, duct work should be attached to the curb prior to installing the unit.
Lower unit carefully onto roof mounting curb. While rigging unit, center of gravity will cause condenser end to be lower than supply
air end.
CIRCULATING AIR AND FILTERS
A
IR FLOW CONVERSION
Units can easily be converted from horizontal to down discharge air flow delivery. In down discharge or high static installations, the
installer should measure the total external static and review the blower performance charts before performing the installation. In
some installations it will be necessary to change the blower speed to provide proper air flow.
Horizontal Air Flow
Single phase models are shipped without horizontal duct covers. If needed, these
kits may be ordered through Goodman’s Service Parts department.
Down Discharge Applications
Cut insulation around bottom openings and remove panels from the bottom of the
unit, saving the screws holding the panels in place.
NOTE: Single phase models require installation of horizontal duct kit #20464501PDGK
(medium chassis) and #20464502PDGK (large chassis).
DUCT WORK
Duct systems and register sizes must be properly designed for the C.F.M. and external
static pressure rating of the unit. Duct work should be designed in accordance with
the recommended methods of Air Conditioning Contractors of America Manual D
(Residential) or Manual Q (Commercial). All duct work exposed to the outdoors must
include a weatherproof barrier and adequate insulation.
A duct system should be installed in accordance with Standards of the National Board
of Fire Underwriters for the Installation of Air Conditioning, Warm Air Heating and
Ventilating Systems. Pamphlets No. 90A and 90B.
The supply duct from the unit through a wall may be installed without clearance. However, minimum unit clearances as shown in
the Appendix must be maintained. The supply duct should be provided with an access panel large enough to inspect the air
chamber downstream of the heat exchanger. A cover should be tightly attached to prevent air leaks.
For duct flange dimensions on the unit refer to the Unit Dimension illustration in the Appendix.
For down discharge applications, the duct work should be attached to the roof curb prior to installing the unit. Duct work dimensions
are shown in the roof curb installation manual.
If desired, supply and return duct connections to the unit may be made with flexible connections to reduce possible unit operating
sound transmission.
FILTERS
Filters are not provided with unit and must be supplied and
externally installed in the return duct system by the installer. A
field-installed filter grille is recommended for easy and
convenient access to the filters for periodic inspection and
Rigging
Remove these panels
for downflow duct
applications
Supply
Return
Duct Cover Installation