280241-YIM-D-0909
Johnson Controls Unitary Products 7
Duct work should be designed and sized according to the
methods of the Air Conditioning Contractors of America
(ACCA), as set forth in their Manual D.
A closed return duct system shall be used. This shall not pre-
clude use of economizers or ventilation air intake. Flexible
joints may be used in the supply and return duct work to min-
imize the transmission of noise.
NOTE: Be sure to note supply and return openings.
Refer to Figures 11 and 12 for information concerning rear
and bottom supply and return air duct openings.
ROOF CURB
On applications when a roof curb is used, the unit must be
positioned on the curb so the front of the unit is tight against
the curb.
FILTERS
Single phase units are shipped without a filter or filter racks. It
is the responsibility of the installer to secure a filter in the
return air ductwork or install a Filter/Frame Kit (1FF0110 for 2
thru 3½ ton units or 1FF0112 for 4 thru 5 ton units).
A filter rack and high velocity filters are standard on three
phase units.
Filters must always be used and must be kept clean. When
filters become dirt laden, insufficient air will be delivered by
the blower, decreasing your units efficiency and increasing
operating costs and wear-and-tear on the unit and controls.
Filters should be checked monthly; this is especially impor-
tant since this unit is used for both heating and cooling.
CONDENSATE DRAIN
A condensate trap is recommended to be installed in the con-
densate drain. The plumbing must conform to local codes.
Use a sealing compound on male pipe threads. Install the
condensate drain line (NPTF) to spill into an open drain.
SERVICE ACCESS
Access to all serviceable components is provided by the fol-
lowing removable panels:
• Blower compartment
• Gas control/electrical service access
Refer to Figure 10 for location of these access panels and
minimum clearances in Table 12.
THERMOSTAT
The room thermostat should be located on an inside wall
approximately 56" above the floor where it will not be subject
to drafts, sun exposure or heat from electrical fixtures or
appliances. Follow manufacturer's instructions enclosed with
the thermostat for general installation procedure. Color coded
insulated wires (minimum #18 AWG) should be used to con-
nect thermostat to unit. See Figures 3 thru 5.
POWER AND CONTROL WIRING
Field wiring to the unit must conform to provisions of the cur-
rent N.E.C. ANSI/NFPA No. 70 or C.E.C. and/or local ordi-
nances. The unit must be electrically grounded in accordance
with local codes or, in their absence, with the N.E.C./C.E.C.
Voltage tolerances which must be maintained at the com-
pressor terminals during starting and running conditions are
indicated on the unit Rating Plate and Table 10.
The wiring entering the cabinet must be provided with
mechanical strain relief.
A fused disconnect switch should be field provided for the
unit. If any of the wire supplied with the unit must be replaced,
replacement wire must be of the type shown on the wiring
diagram.
Electrical line must be sized properly to carry the load. Each
unit must be wired with a separate branch circuit fed directly
from the meter panel and properly fused.
Refer to Figure 6 for typical field wiring and to the appropriate
unit wiring diagram for control circuit and power wiring infor-
mation.
When fastening duct work to the side duct flanges
on the unit, insert the screws through the duct
flanges only. Do not insert the screws through the
casing. Outdoor ductwork must be insulated and
waterproofed.
Hand tighten only.
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