Servicing Unit Delivered Void Of Charge; Unit Start-Up - Lennox XC20-036-230-01 Installation And Service Procedure

Servicing Units Delivered Void of Charge
If the outdoor unit is void of refrigerant, clean the system us­
ing the procedure described below.
1. Leak test the system using the procedure outlined on
page 22.
2. Evacuate the system using procedure outlined on
page 23.
3. Use nitrogen to break the vacuum and install a new fil­
ter drier in the system.
4. Evacuate the system again using procedure outlined
on page 23.
5. Weigh in refrigerant using procedure outlined in figure
56.
6. Monitor the system to determine the amount of mois­
ture remaining in the oil. It may be necessary to replace
the filter drier several times to achieve the required dry­
ness level. If system dryness is not verified, the
compressor will fail in the future.

Unit Start-Up

IMPORTANT
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.
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 to the value listed
in table 1.
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 dis­
connect 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 75.
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XC20