Iv. System Charge; Servicing Unit Delivered Void Of Charge; Unit Start-Up; System Refrigerant - Lennox XP17-024-230-01 Installation And Service Procedure

Servicing Units Delivered Void of Charge
If the outdoor unit is void of refrigerant, clean the system
using the procedure described below.
1. Leak check system using procedure outlined on page
72.
2. Evacuate the system using procedure outlined on
page 74.
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 74.
5. Weigh in refrigerant using procedure outlined in figure
49.
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

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.
GAUGE SET
CONNECTIONS FOR TESTING AND CHARGING
A Close manifold gauge set valves and
connect the center hose to a cylinder of
HFC-410A. Set for
charging.
B Connect the manifold gauge set's low
pressure side to the suction line service
port.
C Connect the manifold gauge set's high
pressure side to the liquid line service
port.
D Position temperature sensor on liquid
line near liquid line service port.
XP17

IV. SYSTEM CHARGE

SUCTION LINE
B
SERVICE PORT
CONNECTION
liquid phase
REFRIGERANT TANK
CHARGE IN
LIQUID PHASE
D TEMPERATURE
SENSOR
Figure 47. Gauge Set Setup and Connections
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 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 under System Refrigerant.

System Refrigerant

This section outlines procedures for:
1. Connecting gauge set for testing and charging.
2. Checking and adjusting indoor airflow.
MANIFOLD GAUGE SET
LOW
A
DIGITAL SCALE
C
TO LIQUID
LINE SERVICE
VALVE
Page 76
HIGH
OUTDOOR UNIT
TEMPERATURE SENSOR
(LIQUID LINE)