First Time Start-Up - York YCRS Series Installation, Operation And Maintenance Manual

pound (Part No. 013-00890-000) and inserted in the
sensor pockets of the cooler. This outlet sensor also
acts as the freeze protection thermostat sensor and must
always be fitted.
Ensure the cooling liquid temperature sensor is coated
with heat conductive compound (Part No. 013-00890-
000) and inserted in the outlet sensor pocket of the
condenser.
Control supply: Verify the control panel display is
illuminated.
HP Cutout Reset: Check that the hand reset mechani-
cal high pressure cutouts mounted on the compressors
are at the correct setting and are reset.
Programmed Options: Verify that the options factory
programmed into the Microprocessor Based Control Sys-
tem are in accordance with the customers order require-
ments by pressing the 'OPTIONS' key on the keypad and
reading the settings from the display. Refer to the MBCS
Section for notes and explanation of messages.
Programmed Settings: Ensure the system cutout and
operational settings are in accordance with the instruc-
tions given in the MBCS Section and with operational
requirements by pressing the 'PROGRAM' key.
Date and time: Program the date and time by first en-
suring that the CLK jumper J18 on the microprocessor
board is in the 'ON' position. Then press the 'SET
TIME/DATE' key and set the date and time (see MBCS
Section).
Start/Stop Schedule: Program the daily and holiday
start/stop by pressing the 'SET SCHEDULE/HOLI-
DAY' key (see MBCS Section).
Setpoints: Set the required leaving chilled liquid tem-
perature setpoint and control range using the 'LOCAL
COOLING SETPOINTS' and 'REMOTE COOLING
SETPOINTS' keys. (see MBCS Section).

FIRST TIME START-UP

During the commissioning period
there should be sufficient heat load to
run the unit under stable full load op-
eration to enable the unit controls, and
system operation to be set up correctly
and a commissioning log taken. Read
the following section in conjunction
with the MBCS Section, then proceed
step by step as follows:
YORK INTERNATIONAL
Interlocks: Verify that liquid is flowing through the cooler
and that heat load is present. Ensure that any remote run
interlocks are in the run position and that the run sched-
ule requires the unit to run or is overridden.
System switches: Set the system 1 switch on the mi-
croprocessor board to the 'ON' position – see operat-
ing sequence in the MBCS Section.
Start-up: Press the 'STATUS' key, and set the toggle
switch to the 'ON' position to start the unit (there may
be a few seconds delay before the first compressor starts
because of the anti-recycle timer). Be ready when each
compressor starts, to switch the unit off immediately if
any unusual noises or other adverse conditions develop.
Use the emergency stop device if necessary. Also refer
to the MBCS Section for the normal operating sequence
from start-up.
Oil Pressure: When a compressor starts, press the rel-
evant 'SYSTEM DATA' key and verify that oil differ-
ential pressure develops immediately. If oil pressure
does not develop, the automatic CONTROLS WILL
shut down the compressor. Under no circumstances
should a restart attempt be made on a compressor which
does not develop oil pressure immediately.
Refrigerant Flow: When a compressor starts a flow of
liquid refrigerant will be seen in the liquid line sight glass.
After several minutes operation and providing a full charge
of refrigerant is in the system, the bubbles will disappear
and be replaced by a solid column of liquid.
Suction Superheat: Check suction superheat at steady
full compressor load only. It is important that no bubbles
show in the liquid line sight glass. Superheat should be
10°F (4°C to 5°C) relative to the 'dew' temperature.
Expansion Valve Adjustment: The expansion valves
are factory set and should not need adjustment. If any
superheat values are out of range, however, the expan-
sion valve adjusting screw should be adjusted no more
than 1 turn at a time ('in' to increase superheat, 'out'
to decrease superheat), allowing at least 10 minutes
for the valve to stabilize before rechecking the value
of superheat.
Subcooling: Check liquid subcooling at steady full
compressor load only. It is important that cooling sys-
tem is operating correctly. Subcooling should be 10°F
relative to the 'bubble' temperature.
General Operation: After completion of the above
checks for system 1 repeat the process for system 2.
When the checks are complete stop the unit, switch
both system switches to the 'ON' position and restart
the unit. Check that loading occurs as specified in the
MBCS and that general operation is correct.
FORM 201.25-NM1 (302)
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