YORK INTERNATIONAL
51
FORM 150.40-NM25
DUAL CIRCUIT UNITS
CONTROL PANEL DATA DISPLAY LETTER CODES
The 4-digit display is capable of providing the operator
with a direct readout of system pressures, temperatures,
and setpoints. This information can be manually selected
and viewed in the “3” rightmost digits of the display. The
leftmost digit automatically displays a letter code indi-
cating system status. Listed below are the meanings of
the letter codes. These codes are also explained in “SYS-
TEM MONITORING or DIAGNOSIS” on the control
panel.
Leftmost Digit no letter (Blank). Informs the opera-
tor that both compressors are ready to run or are
running.
A – Indicates that the Flow Switch is open, time clock
is telling the system to turn off, or a remote cycling
device (EMS, BAS, etc.) is telling the system to turn
off. These are devices whose dry contacts may be
connected in series across terminals 3 and 4 of the
terminal block in the lower left side of the power
section.
c – Shows that System #1 compressor is shut down
and cycling on the 2-minute start-up or 10-minute
anti-recycle timer. It will be available for start or will
restart when the 2-minute start-up and 10-minute
anti-recycle timers time out, and demand allows.
The “c” code will disappear as soon as the timers
time out.*
FIG. 38 – DATA DISPLAY LETTER CODES
*See Page 55 for details on the anti-recycle timers.
d – Shows that System #2 compressor is shut down
and cycling on the 2-minute start-up or 10-minute
anti-recycle timer. It will be available for or will re-
start when the 2-minute start-up and 10-minute
anti-recycle timers time out, and demand allows.
The “d” will disappear as soon as the timers time
out.*
E – Indicates that both compressors are shut down and
cycling on the 2-minute start-up or 10-minute anti-
recycle timer. Both will be available for or will re-
start when the 2-minute start-up and 10-minute anti-
recycle timers time out, and demand allows. The
“E” code will disappear as soon as the timers time
out.*
F – Indicates that a safety threshold has been exceeded
and the unit is shut down on a Fault. Turn the Se-
lect Data Display to “18” to determine the reason
for shutdown. (See list page 52.)
H – Indicates that both of the compressors are off be-
cause cooling demand is not present. The com-
pressor(s) will start as soon as cooling demand is
required. The H code will override c, d, or E code.
LD01867
