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TABLE 3
MANUFACTURER'S NUMBERS
DRIVE
NO.
DRIVE COMPONENTS
ADJUSTABLE SHEAVE
FIXED SHEAVE
BELT
BROWNING NO.
OEM PART NO.
BROWNING NO.
OEM PART NO.
BROWNING NO.
OEM PART NO.
1
1VP34x7/8
31K6901
AK61x1
100244-20
AX54
100245-25
2
1VP40x7/8
79J0301
AK59x1
31K6801
AX55
100245-26
3
1VP34x7/8
31K6901
AK46x1
100244-17
AX52
100245-33
4
1VP44x7/8
53J9601
AK74x1
100244-21
AX58
100245-34
5
1VP50x7/8
98J0001
AK69x1
37L4701
AX58
100245-34
6
1VP50x7/8
98J0001
AK64x1
12L2501
AX57
100245-28
10
1VP50x1-1/8
P-8-1977
BK77x1
49K4001
BX59
59A5001
11
1VP50x1-1/8
P-8-1977
BK67x1
100244-24
BX57
78L5301
12
1VP50x1-1/8
P-8-1977
BK62x1
100244-23
BX56
100245-11
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.
A-Operation
Supply Air Inverter Units - Refer to the Inverter
Start-Up section.
1- Initiate first and second stage cooling demands
according to instructions provided with thermostat.
2-
No Economizer Installed in Unit -
A first-stage cooling demand (Y1) will energize
compressor 1 and both condenser fans. An
increased cooling demand (Y2) will energize
compressor 2.
Units Equipped With Economizer -
When outdoor air is acceptable, a first-stage
cooling demand (Y1) will energize the economizer.
An increased cooling demand (Y2) will energize
compressor 1 and both condenser fans. When
outdoor air is not acceptable unit will operate as
though no economizer is installed.
3- Units contain two refrigerant circuits or stages. See
figure 17.
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.
B-Refrigerant Charge and Check - All-Aluminum Coil
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:
IMPORTANT - Charge unit in standard cooling mode.
1- Make sure outdoor coil is clean. Attach gauge
manifolds and operate unit at full CFM in cooling mode
with economizer disabled until system stabilizes
(approximately five minutes). Make sure all outdoor air
dampers are closed.
FIGURE 17
REFRIGERANT STAGES
1
2
(BOTH FANS ARE ENERGIZED
WITH A Y1 DEMAND)
CONDENSER COIL
KG/KC 092 - Stage 2
KG/KC 102, 120, 150 - Stage 1
EVAPORATOR
COIL STAGE 1
CONDENSER COIL
KG/KC 092 - Stage 1
KG/KC 102, 120, 150 - Stage 2
EVAPORATOR
COIL STAGE 2
