PRE-START-UP
Failure to observe the following warnings could result in
serious injury or death:
1. Follow recognized 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 electri-
cal 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 refrig-
erant 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 fol-
lows:
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 neces-
sary. Oil can ignite when exposed to torch flame.
Proceed as follows to inspect and prepare the unit for initial
startup:
1. Remove access panel.
2. Read and follow instructions on all WARNING, CAUTION,
and INFORMATION labels attached to, or shipped with, unit.
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, halide torch, or liquid-soap solu-
tion. If a refrigerant leak is detected, see Check for
Refrigerant Leaks section under Start-Up.
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.
Verify the following conditions:
a. Make sure that condenser-fan blade is correctly positioned
in fan orifice. Leading edge of condenser-fan blade should
be 1/2 in. maximum from fan orifice (See Fig. 12).
b. Make sure that air filter(s) is in place.
c. Make sure that condensate drain trap is filled with water to
ensure proper drainage.
d. Make sure that all tools and miscellaneous loose parts have
been removed.
START-UP
CHECK FOR REFRIGERANT LEAKS — Proceed as follows to
locate and repair a refrigerant leak and to charge the unit:
1. Locate leak and make sure that refrigerant system pressure has
been relieved and reclaimed from both high- and low-pressure
ports.
2. Repair leak following accepted practices.
NOTE:
Replace filter drier whenever the system has been opened
for repair.
3. Charge unit with R-410A refrigerant, using a volumetric-
charging cylinder or accurate scale.
Refer to unit rating plate
for required charge.
START UP COOLING SECTION AND MAKE ADJUST-
MENTS
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 compres-
sor when the outdoor temperature is below 40°F (unless
accessory low-ambient kit is installed). Do not rapid-cycle the
compressor. Allow 5 min between ‘‘on’’ cycles to prevent
compressor damage.
CHECKING COOLING CONTROL OPERATION — Start and
check the unit for proper cooling control operation as follows:
1. Place room thermostat SYSTEM switch in OFF position.
Observe that blower motor starts when FAN switch is placed
in ON position and shuts down when FAN switch is placed in
AUTO position.
2. Place SYSTEM switch in COOL position and FAN switch in
AUTO position. Set cooling control below room temperature.
Observe that compressor, condenser fan, and evaporator
blower motors start. Observe that cooling cycle shuts down
when control setting is satisfied. The evaporator fan will
continue to run for 30 sec.
3. When using an auto-changeover room thermostat, place both
SYSTEM and FAN switches in AUTO positions. Observe that
unit operates in heating mode when temperature control is set
to ‘‘call for heating’’ (above room temperature) and operates
in cooling mode when temperature control is set to ‘‘call for
cooling’’ (below room temperature).
IMPORTANT:
Three-phase, scroll compressor units (50GL030-
060) are direction-oriented. These units must be checked to ensure
proper compressor 3-phase power lead orientation. If not corrected
within 5 min, the internal protector will shut off the compressor.
Any two of the 3-phase power leads to the unit must be reversed
to correct rotation. When turning backwards, scroll compressors
emit elevated noise levels, and the difference between compressor
suction and discharge pressures may be dramatically lower than
normal.
CHECKING AND ADJUSTING REFRIGERANT CHARGE
— The refrigerant system is fully charged with R-410A refriger-
ant, tested, and factory-sealed.
Fig. 12—Fan Blade Clearance
C99009
FAN GRILLE
MOTOR
1/8" MAX BETWEEN
MOTOR AND FAN HUB
MOTOR SHAFT
1/2˝
11
