035-18548-001-B-0203
10
Unitary Products Group
hole in the sealing discs. If pressure still exists, the cir-
cuit may be considered leak free. If pressure does not
exist the coil should be leak tested.
NOTE:
To minimize the possibility of system failure
due to dirt and moisture, a filter-drier must be
installed in the liquid line as close to the evap-
orator as possible. Filter-driers are not sup-
plied with the evaporator blowers. They are
supplied with the matching condensing sec-
tions.
If solenoid valves are required, they must be pur-
chased and installed in the field. 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 and suction connections must be piped out-
side the unit. Refer to the unit drawing for locations and
the dimensions of these connections.
Before brazing the refrigerant lines to these connec-
tions, remove the short panel from the unit frame and
slide it (along with the grommets) onto the refrigerant
lines. After the brazed joints have cooled, slide the
panel back into place and secure it to the unit frame.
NOTE:
These units can only be piped from one side of
the unit.
EXPANSION VALVE BULB
The expansion valve bulb must be fastened in a 10 or 2
o'clock position to the suction line outside the cabinet
after the piping connections have been made.
Use the clamps provided with the valve to secure the
bulb in position. Bulb must be insulated with armaflex
or mastic 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 the 1-3/8”
knockout in the rear panel, and connect them to the ter-
minals on blower motor contactor 10M. Route the con-
trol wires into the unit through the 7/8” hole in the rear
panel, and connect them to the terminals on block TB1.
Refer to the unit drawing in Figure 14 for the locations
of these knockouts.
Dry nitrogen should flow through the system at
all times when heat is being applied and until
the joint has cooled.
