Unit Start-Up; System Refrigerant - Lennox ML14XC1 Series Manual

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.
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 LIQUID PHASE 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.
REFRIGERANT TANK
CHARGE IN
LIQUID PHASE
DIGITAL SCALE
D
TEMPERATURE
SENSOR
FIGURE 18. Gauge Set Setup and Connections
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 that follow.

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.
NOTE - System fault and lockout codes take precedence
over system status codes (cooling, heating operating per-
centages or defrost/dehumidification).
MANIFOLD GAUGE SET
HIGH
LOW
A
C
TO LIQUID
LINE SERVICE
PORT
Page 27
OUTDOOR UNIT
B
SUCTION LINE
TEMPERATURE SENSOR
(LIQUID LINE)