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PRE-START-UP PROCEDURE
System Check
1. Check all auxiliary components such as the chilled fluid
circulating pump, air-handling equipment, or other equip-
ment to which the chiller supplies liquid. Consult the man-
ufacturer’s instructions. If the unit has field-installed
accessories, be sure all are properly installed and wired
correctly. Refer to the unit wiring diagrams.
2. Check the cooler flow switch for proper configuration and
operation (
from HSIO). Ensure the switch closes
when the pump is on and opens when the pump is turned
off. A flow switch must be installed.
3. Open the discharge and liquid valves in each circuit. The
discharge shutoff valves are in-line ball type and are open
when parallel with the refrigerant flow.
4. If factory-installed suction service valves are installed,
open the suction service valves in each circuit. Service
valve is located below the compressor in the cooler suction
connection flange. To operate the valve, first remove the
cap. Use a back-up wrench on the packing gland to prevent
loosening while removing cap. Loosen the jam nut. Turn
the stem counterclockwise to open. Tighten the jam nut.
5. Open the oil shutoff valves located by the oil pre-filter.
Open bubbler tube valve on 30HX machines equipped
with economizers.
6. Check the tightness of all electrical connections. Check
incoming power supply for proper nameplate voltage.
7. Check to ensure the unit is level per the installation
instructions.
8. Check all field configuration data and set points.
9. Enter correct date, time, and operating schedule(s).
10. Verify operation of solenoids, pumps, valves, compressors,
fans, etc. as listed in the Start-Up Checklist.
11. Open condenser water valves. Check condenser water
pump for proper operation (30HX).
START-UP AND OPERATION
Actual Start-Up —
Actual start-up should be done only
under supervision of a qualified refrigeration mechanic and
qualified Carrier Comfort Network personnel.
1. Set leaving fluid temperature. No cooling range adjustment
is necessary.
2. Start chilled fluid pump and condenser pump (30HXC) if
not controlled by unit.
3. Switch LOCAL/OFF/REMOTE switch to LOCAL or
REMOTE.
4. Provided there is a load on the chiller, allow the machine to
operate and confirm that everything is functioning properly.
Verify that the leaving fluid temperature agrees with the
cooling set point (1 or 2), or if reset is being used, the modi-
fied set point. Chiller is controlling to the Control Point dis-
played under
.
Operating Sequence —
The chiller is started by
switching the LOCAL/OFF/REMOTE switch to either
LOCAL or REMOTE. If cooler pump control is enabled, the
cooler pump is started. If condenser pump control (30HXC) is
enabled, the condenser pump is started. On a command for
cooling, the oil pump is turned on to start the pre-lubrication
process. After 20 seconds, the oil solenoid is opened and the
control reads the oil pressure from the transducer and deter-
mines if sufficient pressure has been built up. If there is not
sufficient pressure, an alarm is generated after the second
attempt and the compressor is not started.
Upon building pressure, the compressor is allowed to start.
For across-the-line (XL) start chillers, the compressor starts
and comes up to full speed within 1 to 3 seconds. For Wye-
Delta start chillers, contactors 1M and S (starter contactor as-
sembly) are closed and the compressor is started in a Wye con-
figuration. This method reduces the locked rotor current re-
quirements by approximately 60% while maintaining enough
torque to bring the compressor up to full speed.
After 5 seconds, the CPM module switches out contactor S
and brings in contactor 2M, which runs the motor in a Delta
configuration (same configuration in which XL units run). The
oil pump will shut off within 10 seconds after the compressor is
started. Once the compressor is successfully running, the con-
trol loads the compressor and adds additional stages of capacity
as needed to satisfy the leaving fluid set point. Head pressure is
controlled by fan cycling (30GX) or can be controlled with a
field installed accessory Motormaster
®
III controller (30GX) or
field installed condenser water valves (30HX).
IMPORTANT: Before beginning Pre-Start-Up or Start-
Up, complete the Start-Up Checklist for the 30GX,HX
Liquid Chillers on pages CL-1 to CL-8. This Checklist
assures proper start-up of the chiller, and provides a
record of unit condition, application requirements, sys-
tem information and operation at initial start-up. The
checklist should be removed from the manual and kept
with the job file for future reference.
IMPORTANT: DO NOT ATTEMPT TO START THE
CHILLER UNTIL THE FOLLOWING CHECKS
HAVE BEEN COMPLETED.
DO NOT make any changes to the factory-installed com-
pressor power wiring in the control box or at the compres-
sor junction box. Doing so will cause permanent damage to
the compressor and will require compressor replacement.
Proper phasing has already been checked at the factory.