Specifications

YORK INTERNATIONAL 29
FORM 160.48-O1
START-UP PROCEDURE
Pre-Starting
Prior to starting the chiller observe the MicroComputer
Control Center. Make sure the display reads
SYSTEM READY TO START
To pre-start the chiller use the following procedure:
1. OIL HEATER - The oil heater must be energized for
12 hours prior to starting the chiller. The unit will not
start if the oil is less than 71°F. If not possible the
compressor oil should be drained and new oil must
be charged into the oil sump. (See “Oil Charging
Procedure”, page 44.)
2. OIL PUMP - To check, press and release the
“MANUAL OIL PUMP” key under “Service” on the
Control Center. The oil pump will run for 10 minutes
and shut down. Press and release the “MANUAL OIL
PUMP” key to stop the operation of the oil pump for
less than 10 minutes of operation.
3. PREROTATION VANES - To perform this test the
starter interlock terminals 3 and 4 must be jumpered
to allow vanes to open (remove the jumper after test).
Make sure the Control Center is in the “SERVICE”
mode, then press the prerotation vanes “OPEN” and
“CLOSE” keys to observe the operation of the
prerotation vanes. The Control Center supplies a sig-
nal to operate the prerotation vanes. The movement
of the vanes will be displayed on the control center.
The display readout is active whenever power is sup-
plied to the control center. Return from the “Service”
mode to “Local”, “Program”, or “Remote” mode to
suit the method of operation selected for the chiller
application. On Variable Speed Drive units, the vanes
may be manually controlled by a switch on the ca-
pacity board in the logic box. Thus, the keypad vane
control keys are non-functional on Variable Speed
Drive units.
4. % CURRENT LIMIT - Press the “% CURRENT
LIMIT” setpoint key on the Control Center. The dis-
play should read
CURRENT LIMIT = 100% FLA
On Solid State Starter units only, the display is
CURRENT LIMIT = 100% FLA, MTR CUR = XXXX FLA
if the Control Center was not programmed. If the set-
point is not 100% and was predetermined for the job
application the Control Center should be pro-
grammed to that specification.
5. All Control Center setpoints should be programmed
before the chiller is started. Prior to start, the clock
must be programmed for the proper day and time.
Any setpoints which are desired to be changed may
be programmed. If not programmed the “default”
value setpoints are as follows:
LCWT = 45°F
% Current Limit = 100% FLA
Pulldown Demand = None
Clock = Sun 12:00A.M.
Daily Schedule = None
Holiday = None
Remote Reset Temp. Range = 20°F
Data Logger = No Operation
Start-Up
1. If the chilled water pump is manually operated, start
the pump. The Control Center will not allow the chiller
to start unless chilled liquid flow is established
through the unit. (A field supplied chilled water flow
switch is required.) If the chilled liquid pump is wired
to the MicroComputer Control Center the pump will
automatically start, therefore, this step is not neces-
sary.
2. To start the chiller, press the “COMPRESSOR
START” switch. This switch will automatically spring
return to the “RUN” position. (If the unit was previ-
ously started press the “STOP/RESET” side of the
“COMPRESSOR” switch and then press the “START”
side of the switch to start the chiller.) When the start
switch is energized the Control Center is placed in
an operating mode and any malfunction will be noted
by messages on the 40 character alphanumeric dis-
play. (See Fig. 17)
Note: Any malfunctions which occur during “STOP/
RESET” are also displayed.
When the chiller is shut down, the prerotation vanes
will close automatically to prevent loading the com-
pressor on start-up. When the prerotation vanes are
fully closed the display will read
SYSTEM READY TO START – VANES CLOSED
when in “SERVICE” mode. When the chiller starts to
operate, the following automatic sequences are ini-
tiated: (Refer to Fig. 18, “Chiller Starting & Shutdown
Sequence”.)
1. The MicroComputer Control Center alphanumeric
display message will read
START SEQUENCE INITIATED
for the first 30 seconds of the starting sequence. (3
min. if Micro Board JP-6 removed)
2. The compressor vent line solenoid valve will open
after the first 5 minutes of unit operation. The sole-
noid will close automatically after the compressor
shuts down.