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On−Board Link W914 DS to R (Figure 4)
On−board link W914, is a clippable connection between ter-
minals DS and R on the integrated control. W914 must be
cut when the furnace is installed with either the Harmony
III
zone control or a thermostat which features humidity
control. If the link is left intact the PWM signal from the Har-
mony III control will be blocked and also lead to control dam-
age. Refer to table 15 for operation sequence in applica-
tions including SLP98UHV, a thermostat which features hu-
midity control and a single−speed outdoor unit. Table 16
gives the operation sequence in applications with a two−
speed outdoor unit.
On−Board Link W951 R to O (Figure 4)
On−board link W951 is a clippable connection between ter-
minals R and O on the integrated control. W951 must be cut
when the furnace is installed in applications which include a
heat pump unit and a thermostat which features dual fuel
use. If the link is left intact, terminal O" will remain ener-
gized eliminating the HEAT MODE in the heat pump.
On−Board Link W915 Y1 to Y2 (Figure 4)
On−board link W915 is a clippable connection between ter-
minals Y1 and Y2 on the integrated control. W915 must be
cut if two−stage cooling will be used. If the link is not cut the
outdoor unit will operate in second−stage cooling only.
Diagnostic LED (Figure 4)
The seven−segment diagnostic LED displays operating sta-
tus, target airflow, error codes and other information. Table
14 lists diagnostic LED codes.
Diagnostic Push Button (Figure 4)
The diagnostic push button is located adjacent to the seven−
segment diagnostic LED. This button is used to enable the
Error Code Recall mode and the Field Test mode. Press the
button and hold it to cycle through a menu of options. Every
five seconds a new menu item will be displayed. When the
button is released, the displayed item will be selected. Once
all items in the menu have been displayed, the menu re-
sumes from the beginning until the button is released.
Error Code Recall Mode
Select "E" from the menu to access the most recent 10 error
codes. Select c" from the Error Code Recall menu to clear
all error codes. Button must be pressed a second time while
c" is flashing to confirm command to delete codes. Press
the button until a solid
≡
" is displayed to exit the Error Code
Recall mode.
Field Test Mode
Use the diagnostic push button to scroll through the menu
as described above. Release the button when the LED
flashes −" to select the Field Test mode.
While in the Field Test mode the technician can:
Initiate furnace ignition and move to and hold low−fire
rate by applying a R to W1 jumper.
Initiate furnace ignition sequence and move to and hold
high−fire rate by applying a jumper from R to W1 and
W2.
Initiate furnace ignition sequence and move to and hold
mid−fire rate by applying a jumper to R and W2.
Apply then remove the jumper from R to W1 and W2 to
change the firing rate from low fire to mid fire and high
fire.
A vent calibration sequence can be initiated even if a
thermostat signal is not present. Press and hold the
push button until a solid C" is displayed. Release the
button and calibration will begin. The furnace will per-
form the high−fire and low−fire pressure switch calibra-
tions and display CAL". After calibration, the LED will
return to the flashing −" display.
During Field Test mode operation, all safety switches are
still in the circuit (they are not by−passed) and indoor blower
performance and timings will match DIP switch selections.
Current furnace firing rate, indoor blower CFM and flame
signal will be displayed. To exit the Field Test mode, press
and hold the button. The menu will resume from the begin-
ning. Also, cycle the main power to exit the Field Test mode.
The integrated control will automatically exit the Field Test
mode after 45 minutes of operation.
