York YCUL0020, Installation, Operation And Maintenance Manual

Page: 111 / 178

JOHNSON CONTROLS
111
SECTION 7 – UNIT CONTROLS
Form 150.63-NM9
Issue date: 5/20/2021
7
Status key
00066VIP
Unit status
Pressing the STATUS key will enable the operator to
determine current unit operating status. The messages
displayed will include running status, cooling demand,
fault status, external cycling device status. The display
will be a single message relating to the highest prior-
ity message as determined by the microboard. Status
messages fall into the categories of General Status and
Fault Status.
The following General, Safety, and Warning messages
are displayed when the STATUS key is pressed. Fol-
lowing each displayed message is an explanation per-
taining to that particular message.
General status messages
In the case of messages which apply to individual
systems, SYS 1 and SYS 2 messages will both be dis-
played and may be different. In the case of single sys-
tem units, all SYS 2 messages will be blank.
U N I T S W I T C H O F F
S H U T D O W N
This message informs the operator that the UNIT switch
on the control panel is in the OFF position which will
not allow the unit to run.
R E M O T E C O N T R O L L E D
S H U T D O W N
The REMOTE CONTROLLED SHUTDOWN mes-
sage indicates that either an ISN system or RCC has
turned the unit “OFF”, not allowing it to run.
D A I L Y S C H E D U L E
S H U T D O W N
The DAILY SCHEDULE SHUTDOWN message in-
dicates that the daily/holiday schedule programmed is
keeping the unit from running.
F L O W S W I T C H / R E M S T O P
N O R U N P E R M
NO RUN PERM shows that either the flow switch is
open or a remote start/stop contact is open in series
with the flow switch. A 3-second delay is built into the
software to prevent nuisance shutdowns due to errone-
ous signals on the run permissive input.
S Y S 1 S Y S S W I T C H O F F
S Y S 2 S Y S S W I T C H O F F
SYS SWITCH OFF tells that the system switch under
OPTIONS is turned “OFF”. The system will not be al-
lowed to run until the switch is turned back ON.
S Y S 1 N O C O O L L O A D
S Y S 2 N O C O O L L O A D
This message informs the operator that the discharge
air temperature is below the point (determined by the
setpoint and control range) that the microboard will
bring on a system or that the microboard has not loaded
the lead system far enough into the loading sequence to
be ready to bring the lag system “ON”. The lag system
will display this message until the loading sequence is
ready for the lag system to start.