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Unit Controls
R E M O T E
P R E S S U R E
This message indicates that the cooling setpoint is un-
der REMOTE control. When under remote control, the
cooling setpoint will be determined by a remote device
such as an ISN control. This message also indicates
that the control point is based on Suction Pressure.
Immediately after the control mode message is dis-
played, the COOLING SETPOINT entry screen will be
displayed. If the unit is programmed for Discharge Air
Temperature the following message will be displayed:
S E T P O I N T
R A N G E
=
(Discharge Air Temperature control)
The above message shows the current Discharge Air
temperature SETPOINT at 55.0°F (notice the cursor po-
sitioned under the number 5). Pressing either the UP or
DOWN arrow will change the setpoint in 0.5°F incre-
ments. After using the UP and DOWN arrows to adjust
to the desired setpoint, the ENTER/ADV key must be
pressed to enter this number into memory and advance
to the RANGE SETPOINT.
This will be indicated by the cursor moving under the
RANGE setpoint. The UP and DOWN arrow keys are
used to set the RANGE, in 0.5 °F increments, to the
desired RANGE setpoint. After adjusting the setpoint,
the ENTER/ADV key must be pressed to enter the data
into memory.
If the unit was programmed for Suction Pressure con-
trol, the following message would be displayed instead
of the previous message.
S Y S
X
S P
=
R A N G E =
+ / -
(Suction Pressure control)
The setpoint and range are programmed with the UP
arrow, DOWN arrow, and ENTER/ADV key as described
in the previous setpoint message. The setpoints in Suc-
tion Pressure Control are the suction pressures of each
individual system on the condensing Unit and will con-
trol to within +/- the cooling range. This method of con-
trol cannot be used unless the unit is equipped with suc-
tion transducers (optional on YCUL0045 - YCUL0185).
112
S U C T I O N
C O N T R O L
=
5 5 . 0 ° F
+ / - 5 . 0 ° F
7 0
P S I G
3
P S I G
On two system units (YCUL0125 - YCUL0275), each
system is controlled independently of each other accord-
ing to its own setpoint and cooling range, so there will
be two similar displays - a setpoint and range for both
system 1 and system 2.
A listing of the limits and the programmable values for
the COOLING SETPOINTS are shown in Table 27.
Both Discharge Air Temperature and Suction Pressure
control are described in detail under the section on Ca-
pacity Control.
Pressing the COOLING SETPOINTS again, after setting
the "local" setpoint(s), will display the remote setpoint
and cooling range. This display automatically updates
about every 2 seconds. Notice that these setpoints are
not "locally" programmable, but are controlled by a re-
mote device such as an ISN control. These setpoints
would only be valid if the unit was operating in the RE-
MOTE mode. The following messages illustrate both Dis-
charge Air Temperature and Suction Pressure control,
respectively.
R E M
S E T P
R A N G E
=
(Discharge Air Temperature control)
R E M
S P X
=
R A N G E =
+ / -
(Suction Pressure control)
Pressing the COOLING SETPOINTS again will bring up
the display that allows the Maximum EMS-PWM Tem-
perature Reset to be programmed. This message is
shown below.
M A X
E M S - P W M
T E M P
R E S E T
The Temp Reset value is the maximum allowable reset
of the Discharge Air Temperature Setpoint. The setpoint
can be reset upwards by the use of a contact closure on
the PWM Temp Reset input (CTB1 terminals 13 - 20)).
See the section on Operating Controls for a detailed
explanation of this feature.
As with the other setpoints, the UP Arrow and DOWN
Arrow keys are used to change the Temp Reset value.
After using the UP and DOWN arrows to adjust to the
desired setpoint, the ENTER/ADV key must be pressed
to enter this number into memory.
=
5 5 . 0 ° F
+ / - 5 . 0 ° F
7 0
P S I G
3
P S I G
R E M O T E
=
+ 2 0 ° F
YORK INTERNATIONAL
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