Page 13
31-5000724 Rev. 0
Figure 6.
Low Fire
Dip Switches
14, 15, 16
High Fire
Dip Switches
17, 18, 19
Airflow Determination
Identify blower speed adjustment points at low and high fire
Airflow will lie on straight line between these two points and will fall within
the shaded area as shown
EXAMPLE -7.5% at low fire +7.5% at high fire
35%
50%
60%
70%
80%
90%
100%
RATE (%)
+15%
+7.5%
-7.5%
-15%
Nominal
-15%
Nominal
-7.5%
+7.5%
+15%
Increasing
Airflow
On-Board Link W914 DS to R (Figure 4)
On-board link W914, is a clippable connection between
terminals DS and R on the integrated control. W914 must
be cut when the furnace is installed with either the zone
control or a thermostat which features humidity control. If
the link is left intact the PWM signal from the control will be
blocked and also lead to control damage. Refer to Table 13
for operation sequence in applications including NF97DM,
a thermostat which features humidity control and a single-
speed outdoor unit. Table 14 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
terminals 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
energized 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
terminals 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
status, target airflow, error codes and other information. LED
codes are listed on Page 16.
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
resumes 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.