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20
PRE-START-UP
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 WARNING, CAU-
TION, 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, or disconnected wires.
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 solution.
c.
Inspect all field- and factory-wiring connections.
Be sure that connections are completed and tight.
Ensure electrical wires do not contact refrigerant
tubing.
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 blades are correctly
positioned in fan orifice. Refer to Outdoor-Fan
Adjustment section on page 22 for more details.
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.
e.
Make sure indoor fan pulley alignment and belt
tension are correct.
START-UP
Unit Preparation —
Make sure that unit has been in-
stalled in accordance with installation instructions and applica-
ble codes.
Return-Air Filters —
Make sure correct filters are in-
stalled in unit (see Tables 1A and 1B). Do not operate unit
without return-air filters.
Outdoor-Air Inlet Screen —
Outdoor-air inlet screen
must be in place before operating unit.
Compressor Mounting —
Compressors are internally
spring mounted. Do not loosen or remove compressor hold-
down bolts.
Internal Wiring —
Check all electrical connections in
unit control boxes; tighten as required.
Refrigerant Service Ports —
Each refrigerant sys-
tem has 4 Schrader-type service gage ports: One on the suction
line, one on the cooling mode liquid line, and 2 on the com-
pressor discharge line. Be sure that caps on the ports are tight.
HIGH FLOW VALVES — Located on the compressor hot gas
and suction tubes are High Flow Valves. Large black plastic
caps distinguish these valves with O-rings located inside the
caps. These valves cannot be accessed for service in the field.
Ensure the plastic caps are in place and tight or the possibility
of refrigerant leakage could occur.
Compressor Rotation —
It is important to be certain
the scroll compressor (size 012 only) is rotating in the proper
direction. To determine whether or not compressor is rotating
in the proper direction:
1. Connect service gages to suction and discharge pressure
fittings.
2. Energize the compressor.
3. The suction pressure should drop and the discharge pres-
sure should rise, as is normal on any start-up.
If the suction pressure does not drop and the discharge pres-
sure does not rise to normal levels:
1. Note that the indoor fan is probably also rotating in the
wrong direction.
2. Turn off power to the unit and tag disconnect.
3. Reverse any two of the unit power leads.
4. Turn on power to the unit, restart compressor.
The suction and discharge pressure levels should now move
to their normal start-up levels.
NOTE: When the compressor is rotating in the wrong direc-
tion, the unit makes an elevated level of noise and does not
provide heating/cooling.
Cooling —
To start unit, turn on main power supply. Set
system selector switch at COOL position and fan switch at
AUTO position. Adjust thermostat to a setting below room
temperature. Compressor starts on closure of contactor.
Reset thermostat at a position above room temperature.
Compressor will shut off.
TO SHUT OFF UNIT — Set system selector switch at OFF
position. Resetting thermostat at a position above room tem-
perature shuts unit off temporarily until space temperature ex-
ceeds thermostat setting.
Compressor restart is accomplished by manual reset at the
thermostat by turning the selector switch to OFF position and
then ON position.
Failure to observe the following warnings could result in
serious personal injury:
1. Follow recognized safety practices and wear protec-
tive 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 all pressure from system before touching or
disturbing anything inside compressor terminal box if
refrigerant leak is suspected around compressor ter-
minals. Use accepted methods to recover refrigerant.
5. Never attempt to repair soldered connection while re-
frigerant 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 and tag
disconnect.
b.
Relieve all pressure from system using both
high- and low-pressure ports. Use accepted meth-
ods to recover refrigerant.
c.
Cut component connection 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.