PRE-START-UP PROCEDURE
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 Check-
list assures proper start-up of the chiller, and provides
a record of unit condition, application requirements,
system 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 NOTATTEMPT TO START THE
CHILLER UNTILTHE FOLLOWING CHECKS HAVE
BEEN COMPLETED.
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
manufacturer’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 option is installed, open the suction
service valves in each circuit. Service valve is located
below the compressor in the cooler suction connection
flange.
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 the incoming power supply for proper phasing.
This can be done by turning on both the line voltage and
control voltage power supplies. Leave the LOCAL/OFF/
REMOTE switch in the OFF position. If the incoming
power is not phased correctly, the CPM will generate
an alarm for voltage phase reversal. Press for
CircuitAand for Circuit B at the HSIO to check
for this alarm. Scroll up and locate the Feedback value
(displayed in units of volts). If a value of 7.0 appears, a
voltage phase reversal has been identified and requires
incoming power supply phase change. If this is the case,
shut down all power supplies and switch any 2 in-
coming power leads at the control box terminal block.
DO NOT make any changes to the factory installed
compressor power wiring in the control box or at
the compressor junction box. Doing so will cause
permanent damage to the compressor and will re-
quire compressor replacement. Proper phasing has
already been checked at the factory.
For those units with 2 incoming terminal blocks, the volt-
age sequence is sensed at one terminal block only. Check
the phasing to ensure that both circuits match.
If the incoming power is still phased incorrectly at the
second terminal block, a current phase reversal alarm
will be generated when an attempt is made to start this
compressor. The compressor will be shut down within
15 milliseconds. To correct this, interchange 2 power
leads at this terminal block only.
9. Check all field configuration data and set points.
10. Enter correct date, time, and operating schedule(s).
11. Verify operation of solenoids, pumps, valves, compres-
sors, fans, etc. as listed in the Checklist.
12. 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 adjust-
ment 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 prop-
erly. Verify that the leaving fluid temperature agrees with
the cooling set point (1 or 2), or if reset is being used, the
modified set point. Chiller is controlling to the Control
Point displayed under .
Operating Sequence — The chiller is started by switch-
ing the LOCAL/OFF/REMOTE switch to either LOCAL or
REMOTE. 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 determines 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
assembly) are closed and the compressor is started in a Wye
configuration. This method reduces the locked rotor current
requirements 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 control loads the compressor and adds addi-
tional 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 Motor-
mastert III controller (30GX) or field installed condenser
water valves (30HX).
If cooler pump control is enabled, the cooler pump is started.
If condenser pump control (30HXC) is enabled, the con-
denser pump is started (Type 1).
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