York YCAS 0138EB, Installation Operation & Maintenance

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JOHNSON CONTROLS
the chiller. The Options key can be used to verify the
Dip Switch positions without looking at or handling the
Microprocessor Board.
Each press of the key will scroll to the next option/dip
switch setting.
Three Option Switch Messages (S1-1 to S1-3) will then
be displayed in sequence. At the end of the sequence,
the display will automatically revert to the first Option
Switch message.
The following is a detailed guide to programming the
Dip Switches together with the associated display mes-
sage provided for each selection when the Options key
is pressed:
SWITCH 1: Water / Brine Cooling
Open:
Water Cooling Mode is for water cooling applications
and allows the chilled liquid leaving temperature set-
point to be programmed from 40 to 70 °F (4 to 21°C).
Selecting this mode also auto-programs the Low Chilled
Liquid Cut-Out at 36°F (2°C) and the Suction Pressure
Cut-Out at 44 PSIG (3 bar).
Closed:
Brine Cooling Mode is for brine/glycol applications with
setpoints below 40°F (4°C) and allows the chilled liquid
leaving temperature setpoint to be programmed from
10 to 70°F (-12 - 21°C). In this mode, the Low Chilled
Liquid Cut-Out can be programmed from 8 to 36° F (-13
to 2°C) and the Suction Pressure Cut-Out programmed
from 20 to 70 PSIG (1 to 5 bar) for R-22 models and 5
to 70 PSIG (0.3 to 5 bar) for R407C models.
SWITCH 2: Ambient Temp. Low Limit
Open:
Standard Ambient Mode auto-programs the Low Ambi-
ent Cutout setting at 25°F (-4°C) and is not adjustable.
S 1 - 2 A M B I E N T C O N T R O L
S T A N D A R D
3.5 MOTOR CURRENT KEY
Pressing the Motor Current key displays compressor
current for each system:
This display shows the average motor current in amps
and average compressor motor current as a percentage
of FLA. All values are approximate. Keep in mind that
current in “amps” is an “approximate” value.
On the second press of the of the Motor Current Key,
the current limit values as set by the ISN (Remote BAS
System) and EMS-PWM current limiting input are
displayed, if they are active. See Sections 1.10, and 2.4
for more details.
3.6 OPERATING HRS / START COUNTER KEY
When the Operating Hours / Starts Counter key is
pressed, the accumulated running hours and starts for
System 1 and 2 compressors are displayed. Where ap-
plicable, pressing the key again displays the values for
Systems 3 and 4 on larger models:
Display Limits : Maximum run hours 99,999
Maximum starts 99,999
Values roll over to zero, if the maximum limit is exceeded.
These counters are zeroed at the fac‑
tory, but may indicate run time and
number of starts logged during factory
testing prior to shipment.
3.7 OPTIONS KEY &
DIP SWITCH SETTINGS
The Options key provides a display of options which are
programmed by the positions of the S1 Dip Switches
on the Microprocessor Board. Proper programming of
the switches is important during the commissioning of
H R S 1 = 1 1 4 3 . 2 = 1 3 8 2
S T R 1 = 2 8 5 . 2 = 3 2 2
H R S 3 = 1 2 5 5 . 4 = 1 0 9 5
S T R 3 = 3 6 5 . 4 = 4 5 5
S 1 - 1 C H I L L E D L I Q U I D
W A T E R
S 1 - 1 C H I L L E D L I Q U I D
G L Y C O L
C O M P 1 = 6 3 A M P 8 5 % F L A
C O M P 2 = 3 0 A M P 4 1 % F L A
I S N C R N T L I M I T : N O N E
E M S C R N T L I M I T : N O N E
Micro Panel Contents