York YLUA0248 Series Installation Operation & Maintenance page 113

Air-cooled scroll condensing units
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FORM 150.73-NM2
ISSUE DATE: 09/07/2020
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.
The low limit, high limit, and default values for the
keys under "SETPOINTS" are listed in Table 14.
Schedule/Advance Day Key
The SCHEDULE is a seven day daily schedule that
allows one start/stop time per day. The schedule can
be programmed Monday through Sunday with an al-
ternate holiday schedule available. If no start/stop
times are programmed, the unit will run on demand,
providing the unit is not shut off on a unit or system
shutdown. The daily schedule is considered "not pro-
grammed" when the times in the schedule are all zeros
(00:00 AM).
To set the schedule, press the SCHEDULE/ADVANCE
DAY key. The display will immediately show the fol-
lowing display.
M O N
S T A R T
S T O P
The line under the 0 is the cursor. It may be changed
by using the UP and DOWN arrow keys until correct.
Pressing the ENTER/ADV key will enter the times and
then move the cursor to the minute box. The opera-
tion is then repeated if necessary. This process may be
followed until the hour, minutes, and meridian (AM
or PM) of both the START and STOP points are set.
After changing the meridian of the stop time, pressing
the ENTER/ADV key will advance the schedule to the
next day.
Whenever the daily schedule is
changed for Monday, all the other
days will change to the new Monday
schedule. This means if the Monday
times are not applicable for the whole
week then the exceptional days would
need to be reprogrammed to the de-
sired schedule.
To page to a specific day press the SCHEDULE/AD-
VANCE DAY key. The start and stop time of each day
may be programmed differently using the UP and
DOWN arrow, and ENTER/ADV keys.
JOHNSON CONTROLS
=
0 0 : 0 0
A M
=
0 0 : 0 0
A M
After SUN (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 display. The first reads:
H O L
S T A R T
S T O P
The times may be set using the same procedure as de-
scribed above for the days of the week. After chang-
ing the meridian of the stop time, pressing the ENTER/
ADV key will advance the schedule to the following
display:
S _ M
T
W
H O L I D A Y
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 * will appear in the space signifying that day as a
holiday. The * can be removed by pressing the DOWN
arrow key.
The Holiday schedule must be programmed weekly
- once the holiday schedule runs, it will revert to the
normal daily schedule.
Program Key
There are ten operating parameters under the PRO-
GRAM key that are programmable. These setpoints
can be changed by pressing the PROGRAM key, and
then the ENTER/ADV key to enter Program Mode.
Continuing to press the ENTER/ADV key will display
each operating parameter. While a particular parameter
is being displayed, the UP and DOWN arrow keys can
be used to change the value. After the value is changed,
the ENTER/ADV key must be pressed to enter the data
into memory. Table 15 shows the programmable limits
and default values for each operating parameter.
Following are the displays for the programmable val-
ues in the order they appear:
D I S C H A R G E
d
C U T O U T
=
DISCHARGE PRESSURE CUTOUT is the discharge
pressure at which the system will shutdown as moni-
tored by the optional discharge transducer. This is a
SECTION 7 – UNIT CONTROLS
=
0 0 : 0 0
A M
=
0 0 : 0 0
A M
T
F
S
N O T E D
B Y
*
P R E S S U R E
5 7 0
P S I G
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