Johnson Controls York YCAL0014E Series, Installation, Operation & Maintenance Instructions Manual

Page: 73 / 216

JOHNSON CONTROLS
73
FORM 150.62-NM6 (103)
SYS SWITCH OFF tells that the system switch under
OPTIONS is turned off. The system will not be allowed
to run until the switch is turned back on.
This message informs the operator that the chilled liq-
uid temperature is below the point (determined by the
setpoint and control range) that the micro will bring on
a system or that the micro has not loaded the lead sys-
tem 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.
The COMPS RUNNING message indicates that the
respective system is running due to demand. The “x”
will be replaced with the number of compressors in that
system that are running.
The anti-recycle timer message shows the amount of
time left on the respective systems anti-recycle timer.
This message is displayed when the system is unable
to start due the anti-recycle timer being active.
The anti-coincidence timer is a software feature that
guards against 2 systems starting simultaneously. This
assures instantaneous starting current does not become
excessively high due to simultaneous starts. The micro
limits the time between compressor starts to 1 minute
regardless of demand or the anti-recycle timer being
timed out. The anti-coincidence timer is only present
on two system units.
When this message appears, discharge pressure limiting
is in effect. The Discharge Pressure Limiting feature
is integral to the standard software control; however
the discharge transducer is optional on some models.
Therefore, it is important to keep in mind that this con-
trol will not function unless the discharge transducer is
installed in the system.
The limiting pressure is a factory set limit to keep the
system from faulting on the high discharge pressure
cutout due to high load or pull down conditions. When
the unload point is reached, the micro will automatically
unload the affected system by deenergizing one com-
pressor. The discharge pressure unload will occur
when the discharge pressure gets within 15 PSIG of
the programmed discharge pressure cutout. This will
only happen if the system is fully loaded and will shut
only one compressor off. If the system is not fully loaded,
discharge limiting will not go into effect. Reloading the
affected system will occur when the discharge pressure
drops to 85% of the unload pressure and 10 minutes
have elapsed.
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
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
S Y S 1 A R T I M E R x x S
S Y S 2 A R T I M E R x x S
S Y S 1 C O M P S R U N x
S Y S 2 C O M P S R U N x
S Y S 1 A C T I M E R x x S
S Y S 2 A C T I M E R x x S
S Y S 1 D S C H L I M I T I N G
S Y S 2 D S C H L I M I T I N G
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