After the Sunday schedule appears on the display a
subsequent press of the 'SCHEDULE/ADVANCE DAY'
key will display the Holiday schedule. This is a two part
message. The first reads:
The times may be set using the same procedure as
described above for the days of the week. After
changing the meridian of the stop time, pressing the
'ENTER/ADV' key will advance the schedule to the
following display:
The line below the empty space next to the 'S' is the
cursor and will move to the next empty space when the
'ENTER/ADV' key is pressed. To set the Holiday, the
cursor is moved to the space following the day of the
week of the holiday and the 'UP ARROW' key is
pressed. An '*' (asterisk) will appear in the space
signifying that day as a holiday. The '*' (asterisk) can be
removed by pressing the 'DOWN ARROW' key.
The holiday schedule must be reprogrammed
after holiday, because once the holiday
schedule runs it will revert to the normal daily
schedule.
7.3
PROGRAM Key
The 'PROGRAM' key is used to set the programmable
cut-outs, timers and switching points. These
parameters can be changed by pressing the
'PROGRAM' key, and then the 'ENTER/ADV' key to
enter the program mode. Continuing to press the
'ENTER/ADV' key will display each operating
parameter. While a particular parameter is being
displayed, the 'UP ARROW' and 'DOWN ARROW' keys
can be used to change the value (Refer to Section 7.5
Cut-out Settings). After the value is changed, the
'ENTER/ADV' key must be pressed to enter the new
parameter into memory .
The programmable parameters are displayed in the
following order:
The discharge pressure cut-out is the pressure at which
the system will shutdown as monitored by the discharge
pressure transducer. This cut-out is backed-up by one
or two (dependant on unit size) mechanical (manual
reset) HP switches located in each refrigerant circuit.
The suction pressure cut-out protects the chiller from an
evaporator freeze-up. If the suction pressure drops
below the cutout point, the system will shut down.
There are some exceptions when the suction
pressure is permitted to temporarily drop
below the cut-out setting. Refer to System
Safeties for details.
The low ambient temperature cut-out sets the chiller
outside ambient temperature cut-out point. If the
ambient temperature falls below this point, the chiller will
shut down. Restart can occur when temperature rises
1.11°C above the cut-out setting.
The low ambient temperature cut-out is not used on
YCWL/YCRL units and must be set to -17.8°C.
The leaving liquid temperature cut-out protects the
chiller from an evaporator freeze-up. Anytime the
leaving chilled liquid temperature drops to the cut-out
point, the chiller shuts down. Restart will be permitted
when the leaving chilled liquid temperature rises 1.11°C
above the cut-out setting.
When water cooling mode is programmed
(‘OPTIONS' key), the cut-out is fixed at 3.0°C
and cannot be changed. Glycol cooling mode
values are programmable.
Each system has its own anti-recycle timers. The
anti-recycle time under the 'PROGRAM' key can be
programmed between 240-600 seconds and sets the
minimum start-to-start time of the lead compressor in a
system. A second non-programmable anti-recycle
timer, stop to start is fixed at 90 seconds, starts to
countdown when the lead compressor in a systems
cycles off. On power up only this timer is set to 120
seconds not 90 seconds.
The anti-recycle message is displayed when a system is
unable to start due to either of the anti-recycle timers
being active (counting down). The actual time displayed
1
-
28
Form 201.26.OI1(11/09)
H O L
S T A R T
=
0 0 :
0 0
A M
S T O P
=
0 0 :
0 0
A M
S
M
T
W
T
F
S
H O L I
D A Y
N O T E D
B Y
*
D I
S C H A R G E
P R E S S U R E
C U T O U T
=
2 6 .
7 B A R G
S U C T I
O N
P R E S S U R E
C U T O U T
=
3 .
0 3
B A R G
L O W
A M B I E N T
T E M P
C U T O U T
= - 1 7 . 8 ° C
L E A V I
N G
L I
Q U I
D
T E M P
C U T O U T
=
2 .
2 ° C
A N T I
R E C Y C L E
T I M E
=
2 4 0
S E C
