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Service Manual -
HRG18xxS1P
508206-01
Issue 2140
Page 29 of 83
Servicing Units Delivered Void of Charge
If the outdoor unit is void of refrigerant, clean the system
using the procedure described below.
1. Leak test the system using the procedure outlined on
Page 17.
2. Evacuate the system using procedure outlined on
Page 17.
3. Use nitrogen to break the vacuum and install a new
filter drier in the system.
4. Evacuate the system again using procedure outlined
on Page 17.
5. Weigh in refrigerant using charging chart on Page 83
or 84.
6. Monitor the system to determine the amount of
moisture remaining in the oil. It may be necessary
to replace the filter drier several times to achieve
the required dryness level. If system dryness is not
verified, the compressor will fail in the future.
Unit Start-Up
If unit is equipped with a crankcase heater, it should
be energized 24 hours before unit start-up to prevent
compressor damage as a result of slugging.
IMPORTANT
1. Rotate fan to check for binding.
2. Inspect all factory- and field-installed wiring for loose
connections.
3. After evacuation is complete, open both the liquid and
vapor line service valves to release the refrigerant
charge contained in outdoor unit into the system.
4. Replace the stem caps and tighten.
5. Check voltage supply at the disconnect switch. The
voltage must be within the range listed on the unit’s
nameplate. If not, do not start the equipment until
you have consulted with the power company and the
voltage condition has been corrected.
6. Set the thermostat for a cooling demand. Turn on
power to the indoor unit and close the outdoor unit
disconnect switch to start the unit.
7. Recheck voltage while the unit is running. Power must
be within range shown on the nameplate.
8. Check system for sufficient refrigerant by using the
procedures listed in the System Refrigerant section on
Page 83 or 84.
WARNING
- Electric Shock Hazard. Can cause injury or death. Unit must be grounded in accordance with national and local codes.
The 4 pins in P6 have the potential of transferring up to 250 volts to the unit cabinet ground.
Designator
Description
Input
Output
Common
SUCT2
Suction Line Temperature Sensor Supply - Pin 2 of 4
2.680k ohms to
327.3k ohms
LIQ1
Liquid Line Temperature Sensor Supply - Pin 3 of 4
2.680k ohms to
327.3k ohms
LIQ2
Liquid Line Temperature Sensor Supply - Pin 4 of 4
2.680k ohms to
327.3k ohms
Table 11. Outdoor Control Terminal Designations and Input /Outputs