Setpoints And Configuration; Unit Operation - York OPTIVIEW YIA D Operation Manual

OptiView Control Center
Software versions (C.OPT.15.xx.yzz) are alpha-numeric
codes that represent the application, language package
and revision levels per below. Each time the controls
portion or language section is revised, the respective
revision level increments.
•
C – Commercial chiller
•
OPT - Used on Microboard 031-02430-000
•
15 – YIA Absorption Chiller
•
xx - controls revision level (00, 01, etc)
•
y – language package (0=English only, 1=NEMA,
2=CE, 3=NEMA/CE )
•
zz – language package revision level (00, 01, etc)
SETPOINTS AND CONFIGURATION OPTIONS
The operating setpoints and configurations can be ac-
cessed thru the OptiView control panel. Modifications to
the setpoints and configurations can only be done from
the OPERATOR or SERVICE level.

UNIT OPERATION

Start and Stop the Unit
The unit can be started using the main switch, using a
remote signal when the unit is in remote mode or by a
scheduled starting.
If the steam or hot water control valve is open less than
10% and the leaving chilled liquid temperature is at or
above setpoint run is initiated and the chilled liquid and
Condenser pump contacts close. The chilled and con-
denser liquid flow switches are bypassed for 30 seconds
each after the respective pump contacts close, or until the
respective flow switch closes, if less than 30 seconds. If
the unit is kept from starting because the leaving liquid
temperature is below setpoint, a cycling shutdown shall
be initiated.
For Low Leaving Chilled Liquid Temperature (LCHLT)
shutdowns only, the system starting temperature is de-
termined by adding 2.0°F(1.1°C) to the leaving chilled
water setpoint.
If the condenser or chilled liquid flow switch does not
close within 30 seconds of the pump contacts closure, a
safety shutdown is performed.
When run conditions are met and flow switches closed for
2 continuous seconds, startup continues as follows:
12
If the unit is equipped with Franklin Pumps, the steam/
hot water shut-off valves are energized and the refrigerant
pump and generator pump (50 Hz Models YIA-10E3 -
YIA-14F3) are started.
If the unit is equipped with Buffalo pumps, refrigerant
pump operation is controlled by float/level switches 1F
and 3F. The refrigerant pump is not started until both
refrigerant level float switches 3F and 1F close and the
"REFRIGERANT PUMP STARTUP DELAY" setpoint
timer has elapsed as follows: The refrigerant level will
rise to a level that causes 3F to close. As the level con-
tinues to rise, it will cause 1F to close. When 1F closes,
the REFRIGERANT PUMP STARTUP DELAY setpoint
timer is started. If 1F remains closed for the duration of
the timer, the refrigerant pump is started when the pro-
grammed delay has elapsed.
After the refrigerant pump has been started, if the refrig-
erant level decreases to the extent that first 1F opens and
then 3F opens, the REFRIGERANT PUMP SHUTOFF
DELAY setpoint timer is started when 3F opens. If 3F
remains open for the duration of the timer, the refriger-
ant pump is shut off after the programmed delay has
elapsed. When the unit first enters SYSTEM RUN or
after a refrigerant pump shutdown has occurred due to low
refrigerant level, the Chiller REFRIGERANT LEVEL
SHUTDOWN setpoint timer is started. The programmed
value is the number of minutes the unit is allowed to run
without the refrigerant pump running. If the refrigerant
pump is not started before the timer has elapsed, a safety
shutdown is initiated.
To assure that both 1F and 3F float/level switches are
operational, the program compares the state of 1F to 3F.
Since each float/level switch closes as the refrigerant level
rises against it and opens when the level decreases below
the device, and 1F is at a higher level than 3F, it is not
possible that 1F would be closed if 3F is still open; unless
one of the switches is malfunctioning. If this condition is
detected, a warning is displayed.
The unit will perform a cycling shutdown without initiat-
ing dilution when LCHLT is less than LCHLT Setpoint
- LCHLT Shutdown Setpoint (see Setpoints Section).
During this shutdown, dilution is initiated if the strong
solution temperature drops below a calculated value for
crystallization. When the local entered LCHLT setpoint
is manually changed, LCHLT must be below both the
new and previous LCHLT setpoint values by the offset
amount to initiate cycling shutdown until 30 minutes
have elapsed from the time of change. After 30 minutes,
low LCHLT cycling shutdown is based only on the new
FORM 155.21-O1 (615)
JOHNSON CONTROLS