System information

16
3. Make the following inspections:
a. Inspect for shipping and handling damages such as
broken lines, loose parts, disconnected wires, etc.
b. Inspect for oil at all refrigerant tubing connections
and on unit base. Detecting oil generally indicates a
refrigerant leak. Leak-test all refrigerant tubing
connections using electronic leak detector, or liquid-
soap solution. If a refrigerant leak is detected, see
following “Check for Refrigerant Leaks” section.
c. Inspect all field and factory-wiring connections. Be
sure that connections are completed and tight.
d. Inspect coil fins. If damaged during shipping and
handling, carefully straighten fins with a fin comb.
4. Verify the following conditions:
a. Make sure that outdoor fan blade is correctly
positioned in fan orifice.
b. Make sure that air filter(s) is (are) in place.
c. Make sure that condensate drain and trap are filled
with water to ensure proper drainage.
d. Make sure that all tools and miscellaneous loose
parts have been removed.
5. Compressors are internally spring mounted. Do not loosen
or remove compressor hold-down bolts.
6. Each unit system has 2 Schrader-type ports, one low-side
Schrader fitting located on the suction line, and one high-
side Schrader fitting located on the compressor discharge
line. Be sure that caps on the ports are tight.
START-UP
Using the Start-Up Checklist supplied at the end of this book,
proceed as follows:
Check for refrigerant leaks
Locate and repair refrigerant leaks and charge the unit as
follows:
1. Use both high- and low-pressure ports to relieve system
pressure and reclaim remaining refrigerant.
2. Repair leak following accepted practices.
NOTE: Install a bi-flow filter drier whenever the system has
been opened for repair.
3. Check system for leaks using an approved method.
4. Evacuate refrigerant system and reclaim refrigerant if no
additional leaks are found.
5. Charge unit with R-410A refrigerant, using a volumetric
charging cylinder or accurate scale. Refer to unit rating
plate for required charge.
Start-up adjustments
Complete the required procedures given in the “Pre-Start-Up”
section before starting the unit. Do not jumper any safety
devices when operating the unit. Do not operate the unit in
Cooling mode when the outdoor temperature is below 13°C,
unless accessory low-ambient kit is installed. Do not rapid-
cycle the compressor. Allow 5 min. between “on” cycles to
prevent compressor damage.
Routing power leads into unit
Use only copper wire between disconnect and unit. The high-
voltage leads should be in a conduit until they enter the duct
panel; conduit termination at the duct panel must be watertight.
Run the high-voltage leads through the power entry knockout
on the power entry side panel. See Figs. 1 and 2 for location
and size. When the leads are inside the unit, run leads up the
high-voltage raceway to the line wiring splice box (see Fig. 12
and 13).
Connecting ground lead to ground lug
Refer to Fig. 16. Connect the ground lead to the chassis using
the ground lug in the wiring splice box.
Routing control power wires (24 V)
Form a drip-loop with the thermostat leads before routing them
into the unit. Route the thermostat leads through grommeted,
low-voltage hole provided in unit into unit control power splice
box (Figs. 1 and 2). Connect thermostat leads to unit control
power leads as shown in Figs. 14 and 15.
The unit transformer supplies 24-V power for complete system
including accessory electrical heater. An automatic-reset circuit
breaker (Fig. 15) is provided in the 24-V circuit; see the
caution label on the transformer or Fig. 16.
PRE-START-UP
WARNING: Failure to observe the following warnings could
result in serious personal injury or death:
1. Follow recognised safety practices and wear protective
goggles when checking or servicing refrigerant system.
2. Do not operate compressor or provide any electric power
to unit unless compressor terminal cover is in place and
secured.
3. Do not remove compressor terminal cover until all
electrical sources are disconnected.
4. Relieve and recover all refrigerant from both high- and
low-pressure sides of system before touching or
disturbing anything inside terminal box if refrigerant
leak is suspected around compressor terminals.
5. Never attempt to repair soldered connection while refri-
gerant system is under pressure.
6. Do not use torch to remove any component. System
contains oil and refrigerant under pressure. To remove a
component, wear protective goggles and proceed as
follows:
a. Shut off electrical power to unit.
b. Relieve and reclaim all refrigerant from system
using both high- and low-pressure ports.
c. Cut component connecting tubing with tubing
cutter and remove component from unit.
d. Carefully unsweat remaining tubing stubs when
necessary. Oil can ignite when exposed to torch
flame.
Use the Start-Up Checklist supplied at the end of this book and
proceed as follows to inspect and prepare the unit for initial
start-up:
1. Remove all access panels.
2. Read and follow instructions on all DANGER,
WARNING, CAUTION, and INFORMATION labels
attached to, or shipped with, unit.