Servicing Units Void Of Charge; Unit Start−Up; System Refrigerant - Lennox XP16 Series Unit Information

Servicing Units 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
21.
2. Evacuate the system using procedure outlined on page
22.
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 22.
5. Weigh in refrigerant using procedure outlined in figure
18.
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
INSIDE OUTDOOR UNIT
A Close manifold gauge set valves and connect the center hose to a cylinder of HFC−410A. Set for liquid phase charging.
B Connect the manifold gauge set's low pressure side to the true suction port. See figure 1 for approximate location of the true suction 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.
TRUE SUCTION PORT
B
CONNECTION
REFRIGERANT TANK
CHARGE IN
LIQUID PHASE
DIGITAL SCALE
D
TEMPERATURE
SENSOR
Figure 15. Gauge Set Setup and Connections
Page 24
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 Charge.

System Refrigerant

This section outlines procedures for:
1. Connecting gauge set for testing and charging;
2. Checking and adjusting indoor airflow;
3. Adding or removing refrigerant.
MANIFOLD GAUGE SET
HIGH
LOW
A
C
TO LIQUID
TEMPERATURE SENSOR
LINE SERVICE
(LIQUID LINE)
VALVE
OUTDOOR UNIT
XP16