Lennox KHA180 - Cooling Start−Up

Page 12
506393−01 11/2010
TABLE 2
MANUFACTURER’S NUMBERS
Drive
No.
H.P.
DRIVE COMPONENTS
RPM ADJUSTABLE SHEAVE FIXED SHEAVE BELTS SPLIT BUSHING
Min Max Supplier No.
OEM Part
No.
Supplier No.
OEM Part
No.
Supplier
No.
OEM Part
No.
Supplier
No.
OEM Part
No.
1 3 535 725 1VP40x7/8 79J0301 BK95X1−7/16 80K1601 BX59 59A5001 N/A N/A
2 3 710 965 1VP40x7/8 79J0301 BK72x1-7/16 100244−13 BX56 63K0501 N/A N/A
3
5
685 865 1VP50x1−1/8 P−8−1977 BK100x1-7/16 39L1301 BX61 93J9801 N/A N/A
4 5 850 1045 1VP65x1−1/8 100239−03 BK110H 100788−06 BX65 100245−08 H−1−7/16 49M6201
5 5 945 1185 1VP60x1−1/8 41C1301 BK90H 100788−04 BX61 93J9801 H−1−7/16 49M6201
6 7.5 850 1045 1VP65x1−3/8 78M7101 BK110H 100788−06 BX66 97J5901 H−1−7/16 49M6201
7 7.5, 10 945 1185 1VP60x1−3/8 78L5501 BK90H 100788−04 BX63 97J5501 H−1−7/16 49M6201
8 7.5 1045 1285 1VP65x1−3/8 78M7101 BK90H 100788−04 BX64 97J5801 H−1−7/16 49M6201
10 10 1045 1285 1VP65x1−3/8 78M7101 1B5V86 78M8301 5VX670 100245−21 B−1−7/16 100246−01
11 10 1135 1365 1VP65x1−3/8 78M7101 1B5V80 100240−05 5VX660 100245−20 B−1−7/16 100246−01
Cooling Start−Up
A−Start−Up
1− Remove coil covers before starting unit.
2− Set thermostat or temperature control device fan
switch to AUTO or ON. Set thermostat or temperature
control device to initiate a first−stage cooling demand.
A first−stage (Y1) cooling demand will energize
compressor 1 and outdoor fans 1 & 2. An increased
cooling demand (Y2) will initiate compressor 2 and
outdoor fans 3 & 4. On units with an economizer,
when outdoor air is acceptable, a first−stage
demand will energize the economizer; a
second−stage demand will energize compressor 1
and outdoor fans 1 & 2.
3− Refrigerant circuits are factory charged with R−410A
refrigerant. See unit rating plate for correct amount of
charge.
4− Units contain two refrigerant circuits or systems. See
figure 8.
B−Refrigerant Charge and Check
WARNING−Do not exceed nameplate charge under any condition.
This unit is factory charged and should require no further
adjustment. If the system requires additional refrigerant,
reclaim the charge,
evacuate the system, and add
required nameplate charge.
NOTE − System charging is not recommended below
60°F (15°C). In temperatures below 60°F (15°C), the
charge must be weighed into the system.
If weighing facilities are not available, or to check the
charge, use the following procedure:
BLOWER
INDOOR COIL
BLOWER
180 & 240 REFRIGERANT CIRCUITS
FIGURE 8
COMPRESSOR 1 COMPRESSOR 2
OUTDOOR
COIL 2
COND.
FAN 1
COND.
FAN 2
COND.
FAN 4
COND.
FAN 3
OUTDOOR COIL 1
1− Attach gauge manifolds and operate unit in cooling
mode with economizer disabled until system
stabilizes (approximately five minutes). Make sure all
outdoor air dampers are closed.
2− Check each system separately with all stages
operating.
3− Use a thermometer to accurately measure the
outdoor ambient temperature.
4− Apply the outdoor temperature to table 3 or 4 to
determine normal operating pressures. Pressures
are listed for sea level applications at 80
F dry bulb
and 67
F wet bulb return air.
5− Compare the normal operating pressures to the
pressures obtained from the gauges. Minor
variations in these pressures may be expected due to