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Once accessed, the display will stay in the password
protected mode until a DISPLAY, PRINT, SETPOINT, or
CLOCK key is pressed.
If the operator attempts to enter an unacceptable value,
the micro will respond with a momentary message
indicating the selected value has been ignored. This error
message is shown below:
O U T
O F
R A N G E
T R Y
A G A I N !
The 21 programmable displays are shown and described
below in the order in which they appear along with the
range of values which the microprocessor will accept for
each. THE PROGRAMMABLE VALUES UNDER THE
PROGRAM KEY MUST BE CHECKED AND PROP-
ERLY PROGRAMMED WHEN COMMISSIONING THE
CHILLER. FAILURE TO PROPERLY PROGRAM
THESE VALUES MAY CAUSE DAMAGE TO THE
CHILLER OR OPERATING PROBLEMS.
REFRIGERANT TYPE
R E F R I G E R A N T
2 2
0 R
1 3 4
The REFRIGERANT TYPE display message allows the
user to program the chiller for the type of chiller. This
MUST be programmed according to the type refrigerant
used in the chiller. Failure to program this value correctly
will cause catastrophic damage to the chiller.
The type of refrigerant used is noted in the Engineering
Data stamped on the unit nameplate. See page 5.
Whenever R22 is programmed, it is required to first key in
a "0". Example: 022.
To program the type of refrigerant, access the password
protected values as described previously. Key in the type
refrigerant and press the ENTER key. The new value will
be entered into memory and the display will advance to
the next user programmable value.
NOTE: The type of refrigerant programmed must match
the refrigerant selected on the S1 Dip Switches
on the Microprocessor Board. These selections
can be viewed by pressing the OPTIONS key
(Page 79). If these two selections do not match,
the following message will appear.
R E P R O G R A M
R E F R I G E R A N T
The chiller will not operate until this situation is corrected.
YORK INTERNATIONAL
T Y P E
2 2
T Y P E
O F
T O
R U N
DISCHARGE PRESSURE CUT-OUT
D I S C H A R G E
C U T O U T
=
The DISCHARGE PRESSURE CUT-OUT is a
microprocessor back-up for the mechanical high pressure
cut-out located in each refrigerant circuit. Typically
chillers with air-cooled condensers should have the cut-
out set at 395 PSIG (275 PSIG for R134a).
To program the DISCHARGE CUT-OUT, access the
password protected values as described previously. Key
in the desired discharge pressure cut-out and press the
ENTER key. The new value will be entered into memory
and the display will advance to the next user
programmable value.
The micro will accept a range of programmable values
between 200 - 399 PSIG (128 - 275 PSIG for R134a) for
this cut-out. For this cut-out to be functional, the
Discharge Pressure Read-out Option must be installed.
More details on this safety are provided in the "System
Safeties" section.
LOW AMBIENT CUT-OUT
L O W
A M B I E N T
C U T O U T
=
The LOW AMBIENT CUT-OUT allows the user to select
the chiller low ambient temperature cut-out point. If the
ambient temperature falls one degree below this point, the
chiller will shut down. Restart can occur, if demand
allows, when temperature rises more than one degree F
above the cut-out. This only applies to outdoor air-cooled
chillers.
For normal ambient applications, the cut-out is set at 25°F
and is NOT programmable. However, some users may
set the cut-out higher to shut down the chiller and take
advantage of other less costly cooling sources. In this
case, S1 Dip Switch #2 on the Micro Logic Board must be
in the CLOSED position for "Low Ambient Control" which
allows programming the cut-out above 25°F.
Low ambient operation capability of less than 25°F is
standard on the chiller. If low ambient operation is required
below 25°F, S1 Dip Switch #2 on the Micro Logic Board
must be in the CLOSED position for LOW AMBIENT
CONTROL which allows programming of the cut-out
between 0 - 50°F. If operation is occasionally needed
below 0°F, the cut-out should be set at 00.0°F. This will
allow operation at any temperature since the micro is only
able to recognize temperatures above 1°F and will never
display temperatures below 1°F.
FORM 201.10-NM1
P R E S S U R E
3 9 5 . 0
P S I G
T E M P
2 5 . 0 ° F
89
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