Carrier 19EF Series, Руководство по запуску и эксплуатации

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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 —
Follow the
steps described in the Initial Start-Up section, page 45.
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 1- and 15-minute start tim-
ers have expired, the start sequence will start. Follow the
procedure described in the Start-Up/Shutdown/Recycle sec-
tion, page 34.
Check the Running System —
After the compres-
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 140 F
(60 C) or refrigerant temperature plug 50° F (27° C) dur-
ing shutdown, and above 110 F (43 C) during compres-
sor operation.
2. The bearing oil temperature accessed on the Status01
table should be 140 to 165 F (60 to 74 C). If the bearing
temperature reads more than 180 F (83 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 anywhere in one of the
two sight glasses when the compressor is running.
At shutdown, oil level should be halfway in the lower
sight glass.
4. The oil pressure should be between 15 and 30 psi
(103 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 mo-
tor cooling line should indicate refrigerant flow and a dry
condition.
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
corresponding 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
requirements.
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 opera-
tion. Pulldown rate can be based on kW rate or tempera-
ture rate. It is accessed on the Equipment Configuration
menu Config table (Table 2, Example 5).
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.
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
attempt 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 cor-
rected.
After Limited Shutdown —
No special preparations
should be necessary. Follow the regular preliminary checks
and starting procedures.
Extended Shutdown —
The refrigerant should be trans-
ferred into a storage vessel in order to reduce machine pres-
sure and possibility of leaks. Maintain a holding charge of
5 to 10 lbs (2.27 to 4.5 kg) of refrigerant within the cooler/
condenser/compressor sections, to prevent air from leaking
into the machine.
If freezing temperatures are likely to occur in the machine
area, drain the chilled water, condenser water, and the pum-
pout condenser water circuits to avoid freeze-up. Keep the
waterbox drains open.
Leave the oil charge in the machine with the oil heater
and controls energized to maintain the oil reservoir tempera-
ture. Open compressor motor disconnect.
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