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035-18525-001-B-0203
10
Unitary Products Group
The temperature required to make or break a brazed
joint is sufficiently high to cause oxidation of the copper
unless an inert atmosphere is provided.
The liquid, suction and drain connections inside the
unit must be piped to the outside. Refer to Unit Dimen-
sions for locations of the access openings in the unit
panel.
The factories for field placement into these access
openings supplies protective grommets.
The blower units are shipped with the coil section side
panels suitable for right hand piping connections when
viewed from the return air side of the unit.
In left hand piping is required, the two panels on the
right side of the coil section can be interchanged with
the single panel on the left side of the coil section.
When left-hand piping connections are installed, the
suction line must be insulated to prevent moisture from
condensing and being carried into the blower section.
EXPANSION VALVE BULB
The expansion valve bulb must be fastened in the 10 or
2 o’clock position to the suction line outside the cabinet
after the piping connections have been made. Use the
clamps supplied with the valve. Bulb must be
insulated with Armaflex or Mystic to assure proper
operation.
POWER AND CONTROL WIRING
Install electrical wiring in accordance with the latest
National Electrical Code (NFPA standard No. 70) and/
or local regulations. The unit should be grounded in
accordance with these codes.
Route the power wires into the unit through one of the
7/8" knockouts in the panel with the supply air opening,
and connect them to the terminals on blower motor
contactor 10M. Route the control wires into the unit
through the other 7/8" knockout, and connect them to
terminals on block TB1.
CONTROL WIRE SIZING.
To determine the total circuit length, add the follow-
ing distances:
1 - Outdoor Unit to Indoor Unit
_____________
2 - Indoor Unit to Thermostat
_____________
3 - Thermostat to Indoor Unit
_____________
4 - Indoor Unit to Outdoor Unit
_____________
5 - Outdoor Unit to Elec. Heater _____________
Total Circuit Length _____________
If the unit includes an electric heat accessory, route the
power wires into heater control box in lieu of the unit.
Refer to the unit drawing in Figure 13 for locations of
these knockouts.
If the unit includes an electric heat accessory, route the
power wires into heater control box in lieu of the unit.
Refer to electric heat instruction Form 035-16602-001
for additional installation information.
NOTE: Three-phase motor rotation may be incorrect
when unit is first started up. Reverse phase
(leads L1 and L2) at contactor to obtain the
correct rotation.
Dry nitrogen should flow through the system at
all times when heat is being applied and until
the joint has cooled.
Wire Size
Maximum Total
Circuit Length
(Feet)
#19 Solid
#18 Solid
#18 Stranded
#16 Stranded
#14 Stranded
#12 Stranded
130
170
180
270
455
730
TABLE 5: ELECTRICAL DATA
Blower Motor HP
Power Supply
FLA
LRA
Maximum Fuse Size Amps
Maximum Wire Length Ft.
2
208-3-60
7.5
49.0
15
103
230-3-60
6.8
55.0
15
126
460-3060
3.4
27.0
15
505