Operating Instructions; Initial Start-Up; Prepare The Machine For Start-Up; To Start The Machine - Carrier 17 Start Up & Operation Manual

OPERATING INSTRUCTIONS

Operator Duties
1. Become familiar with refrigeration machine and related
equipment before operating the machine.
2. Prepare the system for start-up, start and stop the ma-
chine, and place the system in a shutdown condition.
3. Maintain a log of operating conditions and document any
abnormal readings.
4. Inspect the equipment, make routine adjustments, and per-
form a control test. Maintain the proper oil and refriger-
ant levels.
5. Protect the system from damage during shutdown
periods.
6. Maintain the set point, time schedules, and other PIC
functions.
Prepare the Machine for Start-Up —
steps described in the Initial Start-Up section, page 58.

To Start the Machine

1. Start the water pumps, if they are not automatic.
2. On the LID default screen, press the LOCAL or
CCN softkey to start the system. If the machine is in
the OCCUPIED mode, and the 3- and 15-minute start
timers have expired, the start sequence will start. Follow
the procedure described in the Start-Up/Shutdown/
Recycle section, page 45.
Check the Running System —
sor starts, the operator should monitor the LID display and
observe the parameters for normal operating conditions:
1. The oil reservoir temperature should be above 150 F
(66 C) or refrigerant temperature plus 70° F (38° C) dur-
ing shutdown, and above 125 F (52 C) during compres-
sor operation.
2. The bearing oil temperature accessed on the Status01 LID
screen should be 150 to 200 F (65 to 93 C). If the bearing
temperature reads more than 210 F (99 C) with the oil
pump running, stop the machine and determine the cause
of the high temperature. Do not restart the machine until
corrected.
3. The oil level should be visible in the lower sight glass
when the compressor is running.
At shutdown, oil level should be halfway in the lower
sight glass.
4. The oil pressure should be between 18 and 30 psi (124 to
207 kPa) differential, as seen on the LID default
screen. Typically the reading will be 18 to 25 psi (124 to
172 kPa) at initial start-up.
5. The moisture indicating sight glass on the refrigerant
motor cooling line (Fig. 8) should indicate refrigerant flow
and a dry condition.
Follow the
After the compres-
61
6. The condenser pressure and temperature varies with the
machine design conditions. Typically the pressure will range
between 100 and 210 psig (690 to 1450 kPa) with a cor-
responding temperature range of 60 to 105 F (15 to
41 C). The condenser entering water temperature should
be controlled below the specified design entering water
temperature to save on compressor kilowatt require-
ments. The leaving condenser water temperature should
be at least 20° F (11° C) above leaving chilled water
temperature.
7. Cooler pressure and temperature also will vary with the
design conditions. Typical pressure range will be be-
tween 60 and 80 psig (410 and 550 kPa), with tempera-
ture ranging between 34 and 45 F (1 and 8 C).
8. The compressor may operate at full capacity for a short
time after the pulldown ramping has ended, even though
the building load is small. The active electrical demand
setting can be overridden to limit the compressor IkW, or
the pulldown rate can be decreased to avoid a high de-
mand charge for the short period of high demand
operation. Pulldown rate can be based on kW rate or tem-
perature rate. It is accessed on the Equipment Configu-
ration menu Config screen (Table 2, Example 5).
9. On open-drive machines, the oil pump will be energized
once every 12 hours during shutdown periods to ensure
that the shaft seal is filled with oil.

To Stop the Machine

1. The occupancy schedule will start and stop the machine
automatically once the time schedule is set up.
2. By pressing the Stop button for one second, the alarm
light will blink once to confirm that the button has been
pressed, then the compressor will follow the normal shut-
down sequence as described in the Controls section. The
machine will not restart until the CCN or LOCAL soft-
key is pressed. The machine is now in the OFF mode.
NOTE: If the machine fails to stop, in addition to action that
the PIC will initiate, the operator should close the guide vanes
by overriding the guide vane target to zero to reduce ma-
chine load; then by opening the main disconnect. Do not at-
tempt to stop the machine by opening an isolating knife switch.
High intensity arcing may occur. Do not restart the machine
until the problem is diagnosed and corrected.
After Limited Shutdown —
should be necessary. Follow the regular preliminary checks
and starting procedures. Control Power must be maintained
in order to keep oil temperature hot and all control safeties
operational. The oil pump on open-drive machines will op-
erate occasionally to keep the contact seal filled with oil to
prevent refrigerant loss.
No special preparations