CLEARANCES
All units require certain minimum clearances for proper opera-
tion and service. Refer to Figure 4 for these clearances.
WARNING: Do not permit overhanging structures or shrubs to
obstruct condenser air discharge.
Additional height may be required for snow clearance if winter
operation is expected.
POWER AND CONTROL WIRING
Install electrical wiring in accordance with the applicable na-
tional, local and municipal codes. The unit should be grounded
in accordance with these codes.
POWER WIRING
Check the voltage of the power supply against the data on the
unit nameplate. Check the size of the power wire, the discon-
nect switch and the fuses against the data in Table 3.
NOTE: Copper conductors must be installed between the dis-
connect switch and the unit.
Refer to Figure 4 for the location of the power wire access
opening through the front of the unit. This opening will require a
field-supplied conduit fitting.
The field-supplied disconnect switch must be suitable for an
outdoor location. Although it should be installed near the unit,
do NOT secure it to the unit cabinet.
Refer to Figure 3 for typical field wiring.
CONTROL WIRING
Refer to Figure 4 for the location of the control wire access
opening through the front of the unit.
Route the necessary low voltage control wires from the TB1
terminal block inside of the unit control box through this access
opening to the room thermostat and to the evaporator blower
motor controller. Wires #18 AWG (1.0mm
2
) should be used.
The room thermostat should be located on an inside wall ap-
proximately 56" (1420mm) 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 thermostat for general installation procedure.
Refer to Figure 3 for typical field wiring.
COMPRESSOR
Units are shipped with compressor mountings factory-adjusted
and ready for operation.
CAUTION: Do Not loosen compressor mounting bolts.
COMPRESSOR CRANKCASE HEATER
The compressor is equipped with a crankcase heater to pre-
vent refrigerant from mixing with crankcase oil during the
“OFF” cycle. The heaters will be energized when the compres-
sor is not running providing the unit disconnect switch is
closed.
CAUTION: Do not attempt to start the compressor without at
least eight hours of crankcase heat or compressor
damage will occur.
If a unit has just been installed or the unit disconnect switch has
been open for a long period of time, move the system switch on
the room thermostat to the “OFF” position before closing the
unit disconnect switch. Eight hours of crankcase heat are re-
quired to drive the liquid refrigerant out of the compressor bef-
ore the compressor can be started.
035-15406-002-A-0504
4
Unitary Products Group
5 F T . M I N .
FIG. 2 - TYPICAL RIGGING (090 MBH Unit Shown)
5 Ft. (1.5m)
Min.
Unit
Size
(MBH)
Compressor
Condenser
Unit
Weight
(lbs. / kg.)
Charge,
(lbs. / kg.)
(Refrigerant-22)
Fan (Propeller)
Fan Motor
1
Coil
3
Rating
(Tons /
kW)
Cap.
(Stages)
Qty.
Dia.
(in. /
mm)
Nom.
Airflow
(CFM /
m
3
s)
Blades
Qty.
HP / kW
Each
RPM Rotation
2
Face
Area
(Ft.
2
/
m
2
)
Rows
High
Ship. Oper. Holding
Oper.
4
Qty.
Pitch
(Deg.)
090
7.5 /
25.6
1
1
24 /
610
4036 /
2.69
3
29
1
.75 / .56 950
CW
18.7 /
1.7
30
300 /
136
295 /
134
1.75 / .79
10.4 /
4.7
120
10.0 /
34.2
1
2
24 /
610
6584 /
3.58
3
27
2
.50 / .37 950
CCW
23.8 /
2.2
36
435 /
198
430 /
195
2.75 / 1.25
17.7 /
8.1
1
These PSC motors are directly connected to the condenser fans and have inherent protection, ball bearings and a 48 frame.
2
When viewing the shaft end of the motor.
3
These condenser coils are 2 rows deep with 3/8" OD copper tubes and 16 aluminum fins per inch.
4
Includes matched indoor blower unit but no piping. Refer to Table 6 for refrigerant line charge.
TABLE 2 - PHYSICAL DATA
