System Refrigerant; Unit Start−Up - Lennox T?CLASS TPA024S4 Unit Information

GAUGE SET
CONNECTIONS FOR TESTING AND CHARGING
INSIDE OUTDOOR UNIT
Servicing Units Void of Charge18
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
16.
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 procedure outlined in Figure
15.
Unit Start−Up19
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.
TRUE SUCTION PORT
B
CONNECTION
REFRIGERANT TANK
CHARGE IN
LIQUID PHASE
DIGITAL SCALE
D
TEMPERATURE
SENSOR
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.
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.
Figure 13. Gauge Set Setup and Connections
Page 20
MANIFOLD GAUGE SET
HIGH
LOW
A
TEMPERATURE SENSOR
C
(LIQUID LINE)
TO LIQUID
LINE SERVICE
VALVE
3. After evacuation is complete, open the liquid line and
suction line service valves to release the refrigerant
charge (contained in outdoor unit) into the system.
4. Replace the stem caps and tighten as specified in
Operating Service Valves on Page 8.
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 refrigerate by using the
procedures listed under Start−Up and Charging
Procedures.

System Refrigerant20

This section outlines procedures for:
1. Connecting gauge set for testing and charging;
2. Checking and adjusting indoor airflow;
3. Adding or removing refrigerant.
OUTDOOR UNIT
LIQUID LINE
SERVICE
PORT