Lennox KGC Series Unit Information page 29

2 - No Economizer Installed in Unit -
See table 8 for cooling operation.
Units Equipped With Economizer -
When outdoor
combination of
energize the economizer.
COOLING OPERATION - WITH ECONOMIZER for
cooling operation.
TABLE 8
COOLING OPERATION - NO ECONOMIZER
T'Stat Compressors
Y1 Compr. 1 Low
Y1 + Y2 Compr. 1 Low; Compr. 2 On
Y1 + Y2 + Y3 Compr. 1 High; Compr. 2 On
TABLE 9
COOLING OPERATION - WITH ECONOMIZER
T'Stat Compressors
Y1 Off
Y1 + Y2 Compr. 1 Low
Y1 + Y2 + Y3 Compr. 1 High
3 - Units contain two refrigerant circuits or stages. See
FIGURE 20 and FIGURE 21.
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.
air is suitable,
thermostat demands
See TABLE
OD Fans
Both On
Both On
Both On
OD Fans
Off
Both On
Both On
REFRIGERANT STAGES - 092, 102, 120, 150
any
will
CONDENSER COIL
9
KG/KC 092, 102 - Stage 2
KG/KC 120, 150 - Stage 1
EVAPORATOR
COIL STAGE 2
REFRIGERANT STAGES - 150
CONDENSER COIL
STAGES 1 & 2
EVAPORATOR
COIL STAGE 2
Page 29
CONDENSER COIL
KG/KC 092, 102 - Stage 1
KG/KC 120, 150 - Stage 2
(BOTH FANS ARE ENERGIZED
WITH A Y1 DEMAND)
2
1
FIGURE 20
TUBE/FIN OD COIL
(BOTH FANS ARE ENERGIZED
WITH A Y1 DEMAND)
2
1
EVAPORATOR
COIL STAGE 1
FIGURE 21
EVAPORATOR
COIL STAGE 1