56 YORK INTERNATIONAL
DUAL CIRCUIT UNITS
“OPTIONAL” REMOTE TEMPERATURE SETPOINT
RESET
Remote Temperature Setpoint Reset capabilities can be
added by adding an optional Digital Input Board and con-
figuring a switch on the Micro Logic Board (SW 4; ON).
See Fig. 50 & 51 for location and switch positioning.
Temperature Setpoint changes are accomplished by
closing the “dry” contacts between terminals 75 & 76 of
TB8 on the lower left of the power panel for a defined
period of time. The lowest setpoint temperature desired
must be set on the panel via the “Chilled Water Temp.
Select” rotary switches. Two reset ranges are available
depending upon whether the unit is equipped for stand-
ard or brine duty.
Standard Water Duty. Setpoint = 40°- 70°F
GEII.5 REV.2 (English) **
Installed On Micro Logic Board
To change the setpoint, “dry” contacts between terminals
75 & 76 must be closed for a period between 1 and 11
seconds. Closure for a period shorter than 1 second will
be ignored by the Micro Logic Board. Closure slightly
longer than 11 seconds will be treated as 11 seconds.
The contact closure corresponds to a positive offset (rise)
from the setpoint on the panel. 1 sec. = + 0° offset and
11 sec. = +15°F or offset = 1.5 (time closed – 1 sec.)
Example: A setpoint of 51°F on the panel and a contact
closure of 4.33 sec. will result in an offset of + 5°F. This
raises the RWT setpoint to 56°F.
To maintain the remote setpoint described above, the
EMS Pulse Width Modulation input (terminals 75 & 76)
on the Digital Input Board must be refreshed every 30
minutes or less (20 minutes is recommended). In other
words, to maintain the 56°F RWT setpoint, the contacts
between terminals 75 & 76 must be closed for a period
of 4.33 seconds every 20 minutes. If this is not refreshed
at least every 30 minutes, the Micro Logic Board will
take this as a signal to change the RWT setpoint back
to the original setpoint of 51°F on the Control Panel.
Brine Duty Setpoint = 15°* to 70°F (–9.4° to 21.1°C)
GEII.5 BR REV.1 (English) or GEII.5M REV.1 (Metric)
EPROM Installed In Micro Logic Board
To change the setpoint, “dry” contacts between terminals
75 & 76 must be closed for a period between 1 and 21
seconds. Closure for a period shorter than 1 second will
be ignored by the Micro Logic Board. Closure slightly
longer than 21 seconds will be treated as 21 seconds.
The contact closure corresponds to a positive offset (rise)
from the setpoint on the panel. 1 sec. = +0° offset and
21 sec. = +40°F (4.4°C) or Offset = 2 (time closed – 1
sec.). Note: Metric Offset = 1.11 (time closed – 1 sec.).
For example: A setpoint of 25°F (–3.9°C) on the panel
and a contact closure of 8.5 sec. will result in an offset
of 15°F (8.33°C). This raises the RWT setpoint to 40°F
(4.4°C).
To maintain the remote setpoint described above, the
EMS Pulse Width Modulation input terminals 75 & 76 of
TB8 must be refreshed every 30 minutes or less (20
minutes is recommended). In other words, to maintain
the 40°F (4.4°C) RWT setpoint, the contacts between
terminals 75 & 76 must be closed for a period of 8.5
seconds every 20 minutes. If this is not refreshed at least
every 30 minutes’ the Micro Logic Board will take this as
a signal to change the RWT setpoint back to the original
setpoint of 25°F (–3.9°C) on the Control Panel. See EMS/
BAS Option in “OPTIONS” Section for more information.
“OPTIONAL” REMOTE UNLOADING AND DEMAND
LIMITING
A forced unload of the system, independent of water
temperature demand, can be accomplished by closing
a “dry” contact connected between terminals 73 & 74 of
TB8 on the lower left of the power panel. This control
feature forces turn-off of the lag compressor. Note:
Switch 4 must be in the “ON” position on the Micro Logic
Board. (See Fig. 50.) See EMS/BAS Option in “OP-
TIONS” Section for more information.
ANNUNCIATION ALARM CONTACTS (OPTIONAL)
YORK can supply alarm kits whose contacts will transi-
tion to function as a warning if unit malfunction occurs.
A 110VAC or 28VDC volt external alarm circuit (by oth-
ers) must be wired into the YORK supplied alarm cir-
cuit. If the alarm circuit is applied to chillers used for
critical duty (such as process duty, or cooling other criti-
cal equipment) and the alarm circuit should fail to func-
tion, YORK will not be liable for damages.
See Alarm Option in “OPTIONS” Section for more infor-
mation.
*Leaving water temperatures of below 15°F (–9.4°C) are not per-
mitted, regardless of whether leaving or return water temperature
control is selected.
**The GEII.5 REV.2 may also be labeled GEII.5S REV.2. These 2
EPROMs are identical.
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