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START-UP
CAUTION
To prevent injury, ensure that ducting or wire fan guards are
installed on the condenser fan before starting the unit.
General
Complete the start-up checklist on pages CL-1 and CL-2 before
attempting system start-up.
System Evacuation and Dehydration
Refer to GTAC II, Module 4, ''Dehydration for Proper Evacuation
and Dehydration Techniques.''
Charging Procedure
Before charging the system, install or replace the filter drier(s)
connected to the liquid line in the indoor unit to prevent contami-
nation within the system. Refer to GTAC II, Module 5 "Charging,
Recovery, Recycling, and Reclamation" for proper charging tech-
niques.
Low Ambient Operation (Factory Installed)
Refrigerant pressure controlled VFD (variable frequency drive)
adjusts fan speed to control head pressure. This fan speed control
permits unit to operate in cooling even in winter, when outdoor-air
temperature is down to 0°F.
The refrigerant pressure is measures by a discharge pressure trans-
ducer that is factory-installed.
Configuration of Low Ambient Kit
(Field Installation)
The original unit should have the wiring diagrams as shown in the
typical wiring schematic in Troubleshooting section. The motor
start and wiring should be replaced with a 24-v relay and the VFD,
with the wiring shown in either the typical wiring schematic for
low ambient option (09XC06,08 units) or typical wiring schemat-
ic for low ambient option (09XC12-24 units). Wiring diagrams are
provided in Troubleshooting section.
Be sure the VFD jumper wires are set as shown in the wiring dia-
gram and the two DIP switches are set to the "0" position for volt-
age control.
The parameters shown in Table 5 must be set for low ambient op-
eration. Use actual nameplate motor FLA value since this value is
subject to change.
When the drive is installed and wired, it will be necessary to con-
figure the drive for this application, as follows:
1.
When the drive first starts, system will prompt to run the
Carrier Configuration Assistant. Exit this option.
2.
Configure the drive parameters by pressing the menu button
and using the arrow keys to select "Parameters", then press
the enter key.
3.
Move to the appropriate sub-group using the arrow keys (first
two digits of the parameter to be changed), then press <SEL>.
4.
Select the parameter to view or change using the arrow keys.
Change a parameter by scrolling to that parameter and press-
ing <EDIT>.
5.
Select the New Value, then press <SAVE>.
Table 5 — Low Ambient Operation Parameters
PARAMETER
PARAMETER FUNCTION
INDEX
9902
Application Macro
9906
Motor Nominal Voltage
9907
Motor Nominal Current
9908
Motor Nominal Speed
9909
Motor Nominal Power
1102
EXT 1 - EXT 2 SEL
1301
AI-1 Minimum
1302
AI-1 Maximum
1304
AI-2 Minimum
1305
AI-2 Maximum
1501
AO1 Content
2007
FREQUENCY MIN
2202
Acceleration Time
2203
Decel Time
OUTPUT 1
3404
DISPLAY FORM
OUTPUT 2
3408
PARAMETER
3409
SIGNAL 2 MIN
3410
SIGNAL 2 MAX
3412
OUTPUT 2 UNITS
3413
OUTPUT 2 MIN
3414
OUTPUT 2 MAX
3415
OUTPUT 3 PARAMETER
3416
SIGNAL 3 MIN
3417
SIGNAL 3 MAX
3419
OUTPUT 3 UNITS
3420
OUTPUT 3 MIN
3421
OUTPUT 3 MAX
4001
PID GAIN
4002
PID INTEGRATE
4003
DERIVATION TIME
4005
ERROR VALUE INVERTED
4006
4008
0% VALUE
4009
100 % VALUE
4010
SET POINT SELECT
4011
INTERNALSET POINT
4014
Feedback Select
4017
ACT-2 Input
Check Operation of Condenser Fan Motor
Controls and Rotation of Fans
Rotation should be clockwise as viewed from belt access panel.
IMPORTANT: Check for proper fan rotation. If rotation needs
to be reversed, disconnect main power supply and switch any
2 leads at the load side of the disconnect switch.
Adjust Fan Speed
The 09XC units are belt-driven condenser units and allow for a
wide range of inlet static and condenser airflow requirements. It
may be necessary to adjust the condenser airflow to account for
these inlet conditions. Inadequate airflow will result in poor unit
performance and possible nuisance tripping of high-pressure
switches.
If an airflow is not specified, use the nominal airflow from Table 2
and adjust the fan speed to compensate for actual job conditions.
Use Tables 6-11 to determine proper fan speed. If the unit trips on
high pressure due to high condensing temperature, then it may be
necessary to increase the fan speed and condenser airflow.
8
SELECTION
1 (HVAC Default)
Unit Voltage
(use value on nameplate)
Motor FLA
(use value on nameplate)
1750
Motor HP
(use value on nameplate)
EXT 2
5%
45%
5%
45%
122 (RO1-3 Status)
30.0 HZ
10 s
11 s
Direct
PID 1 SETPOINT
0.0 PSI
667.0
PSI
0.0 PSI
667.0
PID 1 FEEDBACK
0.0 PSI
667 PSI
PSI
0.0 PSI
667 PSI
0.7
5 s
DISABLE
YES
UNITS
PSI
0.0 PSI
667 PSI
INTERNAL
300.0
7 [Max(A1, A2)]
1 (AI1)
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