Specifications

20 YORK INTERNATIONAL
and it says that there have been 7 purges in the
“Last Hour”, that means that there have been 7
exhausts since 8:11 AM. If you do this at 2:57
PM, it means that there have been 7 exhausts
since 1:57 PM, etc.
The purge count is reset to zero by:
A. Clearing the excess purge message.
B. Moving the Micro Board program jumper
J-57 (CLK ON/OFF) from “CLK OFF” to
CLOCK ON” position.
C. Starting the chiller.
The purge count is frozen by the following:
A. When the chiller is not running.
B. An excess purge message is being dis-
played and at least 1 full hour of purge
exhausts have accumulated.
HISTORY PRINT - This key is used to initiate a history
print to the optional printer. Refer to Form 160.48-NO1.2
for operation of this key.
OPERATING MODES
The MicroComputer Control Center can be operated in
four different operating modes as follows:
SERVICE - Enables all the Service keys except “DIS-
PLAY DATA”, “MANUAL OIL PUMP”, and “HISTORY
PRINT”, which are enabled in all modes. See “Service
Keys”, page 18.
LOCAL - This is the normal operating mode. The com-
pressor can be started and stopped from the Control
Center. Also, the Display and Setpoints parameters can
be displayed.
PROGRAM - Allows the operator to program the
Setpoints parameters, and change operating modes.
REMOTE - In this mode, the Control Center will accept
control signals form a remote device (i.e., Energy Man-
agement System) or cycling inputs. The control signal
inputs are:
1. Remote Start
2. Remote Stop
3. Remote LCWT Setpoint
4. Remote Current Limit Setpoint
NOTE: The compressor can be stopped by the “COM-
PRESSOR” switch, regardless of the operating
mode. The switch must be in “RUN” position to
enable “REMOTE” mode. The operator cannot
locally start the compressor using the “COM-
PRESSOR” switch when in the “REMOTE”
mode.
To determine which operating mode the Control Center
is presently in, simply press the “MODE” key.
• If the Control Center is in “LOCAL” mode, this is
displayed:
LOCAL OPERATING MODE IN EFFECT
• If the Control Center is in “REMOTE” mode, this is
displayed:
REMOTE OPERATING MODE IN EFFECT
• If the Control Center is in “SERVICE” mode, this is
displayed:
SERVICE OPERATING MODE IN EFFECT
To change operating mode, proceed as follows:
1. Press “ACCESS CODE” key.
2. This message appears:
ENTER VALID ACCESS CODE __ __ __ __
3. Using “Entry” keys, enter 9 6 7 5.
4. As each digit is entered, the characters Y O R K are
displayed.
NOTE: If digits other than 9 6 7 5 are entered,
Y O R K is still displayed.
5. Press “ENTER” key.
NOTE: If digits other than 9 6 7 5 were entered in step
No. 4,
INVALID ACCESS CODE
is displayed when the “ENTER” key is pressed.
If this occurs, enter the correct access code
(9 6 7 5) and proceed.
6. This message is displayed:
ACCESS TO PROGRAM KEY AUTHORIZED
NOTE: Unless terminated by pressing the “ACCESS
CODE” key again, the operator will have ac-
cess to the “PROGRAM” key for 10 minutes.