Placement And Installation; Start Up Operation - Lennox KCC Series Unit Information

II-PLACEMENT AND INSTALLATION
Make sure the unit is installed in accordance with the
installation instructions and all applicable codes. See
accessories section for conditions requiring use of the
optional roof mounting frame.
III-STARTUP - OPERATION
Refer to startup directions and to the unit wiring diagram
when servicing. See unit nameplate for minimum circuit
ampacity and maximum fuse size.
A-Preliminary and Seasonal Checks
1 - Make sure the unit is installed in accordance with
the installation instructions and applicable codes.
2 - Inspect all electrical wiring, both field and factory
installed for loose connections. Tighten as required.
Refer to unit diagram located on inside of unit
control box cover.
3 - Check to ensure that refrigerant lines are in good
condition and do not rub against the cabinet or
other refrigerant lines.
4 - Check voltage at the disconnect switch (if applicable)
or TB2. Voltage must be within the range listed on
the nameplate. If not, consult the power company
and have the voltage corrected before starting the
unit.
5 - Recheck voltage and amp draw with unit running. If
voltage is not within range listed on unit nameplate,
stop unit and consult power company. Refer to unit
nameplate for maximum rated load amps.
6 - Inspect and adjust blower belt (see section on
Blower Compartment - Blower Belt Adjustment).
B - Cooling Start Up
IMPORTANT
If unit is equipped with a crankcase heater. Make sure
heater is energized 24 hours before unit start- up to
prevent compressor damage as a result of slugging.
Supply Air Inverter Units - Refer to the Inverter Start-Up
section for further instruction on blower control.
Compressor 1 is a two-stage compressor. Compressor 2
is a single-stage compressor.
1 - Initiate first, second, and third stage cooling
demands according to instructions provided with
thermostat.
2 - No Economizer Installed in Unit -
See TABLE 4 for cooling operation.
Units Equipped With Economizer -
When outdoor
combination of
energize the economizer.
COOLING OPERATION - WITH ECONOMIZER for
cooling operation.
air is suitable,
thermostat demands
See TABLE
COOLING OPERATION - NO ECONOMIZER
T'Stat
Y1
Y1 + Y2
Y1 + Y2 + Y3 Compr. 1 High; Compr. 2 On
COOLING OPERATION - WITH ECONOMIZER
T'Stat
Y1
Y1 + Y2
Y1 + Y2 + Y3
3 - Units contain two refrigerant circuits or stages. See
FIGURE 14 and FIGURE 151.
4 - Each refrigerant circuit is separately charged with
R-410A refrigerant. See unit rating plate for correct
amount of charge.
5 - Refer to Cooling Operation and Adjustment section
for proper method to check refrigerant charge
Three Phase Scroll Compressor Voltage Phasing
Three phase scroll compressors must be phased
sequentially to ensure correct compressor and blower
rotation and operation. Compressor and blower are wired
in phase at the factory. Power wires are color-coded as
follows: line 1-red, line 2-yellow, line 3-blue.
1 - Observe suction and discharge pressures and
blower rotation on unit start-up
If pressure differential is not observed or blower rotation
is not correct:
2 - Suction pressure must drop, discharge pressure
must rise, and blower rotation must match rotation
marking.
3 - Disconnect all remote electrical power supplies.
4 - Reverse any two field-installed wires connected to
the line side of TB2 or F4. Do not reverse wires at
VFD or compressors.
5 - Make sure the connections are tight.
Discharge and suction pressures should operate at their
normal start-up ranges.
any
will
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TABLE 4
Compressors
Compr. 1 Low
Compr. 1 Low; Compr. 2 On
TABLE 5
Compressors
Off
Compr. 1 Low
Compr. 1 High
OD
Fans
Both On
Both On
Both On
OD Fans
Off
Both On
Both On