York YCAS Series, Installation Operation & Maintenance

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174 YORK INTERNATIONAL
FORM 201.19-NM8 (804)
Key in the desired Chilled Liquid Setpoint and the
al low able deviation (Range). The micro will accept
val ues from 10.0 - 70.0°F (-12 to 21°C). For values
below 40°F (4.4°C), Dip Switch S1, Switch #1 on the
Mi cro pro ces sor Board must be properly programmed
for Glycol Cooling (see Section 3.7). If unacceptable
val ues are entered, or the switch is incorrectly selected
when setpoints below 40°F (4.4°C) are entered, the fol-
low ing message will be displayed before returning to
the Con trol Range message:
After the Setpoint is keyed in, the cursor will au to mat i-
cal ly advance to the fi rst digit of the Range as shown:
This value should be programmed for the maximum de-
sirable positive and negative chilled liquid tem per a ture
deviation that is acceptable from setpoint for the system
application. A typical value would be +/- 2.0°F (1.1°C).
The micro will accept a range from 1.5 - 2.5°F (0.9 to
1.4°C).
After the Setpoint and Range is keyed in, press the
ENTER Key to store the data in memory.
Failure to press the Enter key will
cause the new ly programmed values
to be ig nored and not en tered into
mem o ry.
After pressing the Enter key, the display will continue
to show the message until another key is pressed.
6.4 REMOTE COOLING SETPOINTS KEY
Remote Cooling Setpoints key allows resetting the set-
point upward from the programmed value in mem o ry
from a remote device. This feature is typically used for
demand limiting or ice storage applications. Reset is
accomplished by timed closure of external con tacts for
a defi ned period of time and allows reset of the set point
upward by up to 40°F (22°C) above the setpoint pro-
grammed in memory – see Section 1.7.
The maximum allowable reset must be programmed into
memory and can be a value of 2 to 40°F (1 to 22°C) de-
pending on user requirements. To program the maximum
reset, press the Remote Reset Temperature Range key.
The following message will appear:
The display indicates the Remote Setpoint which is
al ways equal to the chilled liquid setpoint programmed
by the Chilled Liquid Temperature/Range key plus the
off set from the remote reset signal. The display will also
show the Range which is the programmed max i mum de-
viation allowed for the application. The RANGE dis play
is not programmable, and only the setpoint will change
as a result of a signal from a remote device.
Pressing the REM RESET TEMP RANGE Key again
scrolls the display to the MAX EMS-PWM REMOTE
TEMP RESET which is programmable. This should be
programmed to the maximum offset which is required
for the application. The maximum programmable val ue
is 40° F (22°C), while the minimum programmable val ue
is 2°F (1.1°C).
The cursor will stop beneath the fi rst digit of the max-
i mum reset. Key in the maximum reset allowed for the
application, remembering to use a leading “0” for val ues
less than 10°F (or 5.6°C). Press the ENTER Key to store
the new value in memory.
O U T O F R A N G E -
T R Y A G A I N !
S E T P O I N T = 4 4 . 0 ° F
R A N G E = + / - 2 . 0 ° F
R E M S E T P = 4 4 . 0 ° F
R A N G E = + / - 2 . 0 ° F
M A X E M S - P W M R E M O T E
T E M P R E S E T = + 4 0 ° F
OIL TEMPERATURE ANTICIPATORY SHUTDOWN
CONTROL
If the oil temperature nears the safety shutdown point,
the micro may turn off the compressor to avoid a high
oil temperature fault.
If the oil temperature rises above 220ºF (104ºC) and
SV position is <60 steps, the micro will pump down the
compressor and shut it off. The micro will not allow the
affected system to restart for a period of 15 minutes. A
message indicating the compressor start inhibit will be
displayed. An example of the display is shown below.
6.3 LOCAL COOLING SETPOINTS KEY
The Local Cooling Setpoints key is used to program the
required Leaving Chilled Liquid control tem per a tures
for the application. When the key is pressed, the fol-
low ing message will be displayed:
S E T P O I N T = 4 4 . 0 ° F
R A N G E = + / - 2 . 0 ° F
Micro Panel Contents
S Y S # D S C H / O I L I N H I B
S Y S # D S C H / O I L I N H I B