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S9240F2051 MODULATING INTEGRATED FURNACE CONTROL
25
69-2807—01
Field Test Mode
In Field Test Mode you can:
• Initiate furnace light-off sequence and move to and hold
low firing rate by applying a W1 signal.
• Initiate furnace light-off sequence and move to and hold
high firing rate by applying a W1+W2 signal.
• Initiate furnace light-off sequence and move to and hold
mid firing rate by applying a W2 signal.
• Change the furnace firing rate between low, mid, and high
by applying and removing W1 and W2 signals.
NOTE: Removal of both W1 and W2 at the same time
will cause the furnace to shut down.
• Initiate the pressure switch calibration sequence
regardless if thermostat signals are present. The furnace
performs the low and high pressure switch calibrations and
displays “C A L” on the LED. After calibration, the LED
returns to the flashing “–” display.
No safety control or other safety related parameters are
bypassed during Field Test Mode.
Normal routines (like changing CAI speed if the high pressure
switch opens, etc.) are retained as active while in Field Test
Mode.
Indoor blower performance and timings will match dip switch
selections.
Error code recall and clearing is not available in Field Test
Mode.
Field Test Mode is exited by: pressing the push button, cycling
main power, or after 45 minutes with no activity in Field Test
Mode.
System Status
Table 11 describes the possible System Status LED displays.
Table 9. LED Menu Actions.
LED Display Sequence
Action When Pushbutton Is
Released
Idle Menu Options
No change
a
a
No Change: The display continues to show whatever is cur-
rently being displayed for normal operation (blinking decimal,
active error code, heat/cool state, etc…).
Remain in idle mode
Solid “
E
”
Enter diagnostic recall mode
Solid “
–
” (dash)
Enter field test mode
Diagnostic Recall Menu Options
No change
(displaying error history)
Remain in diagnostic recall mode
Solid “
≡
”
(
3 horizontal bars) Exit diagnostic recall mode
Solid “
C
” (for 10 seconds)
Clear error history
b
b
Clear Error History: Once the button is released, a blinking
“C” displays for up to 10 seconds. During this time you must
press and release the button one additional time to confirm
the action of deleting the error history. If the IFC is in a lockout
state, the IFC proceeds to the IDLE state after the error his-
tory is cleared.
Once the error history is deleted, it cannot be
recovered.
Field Test Menu Options
No change (blinking “
–
”)
Remain in field test mode
Solid “
–
” (dash)
Exit field test mode
Solid “
C
”
Start pressure switch calibration
c
c
If the IFC is in one of the lockout states and a pressure switch
calibration is initiated by the push button, the IFC proceeds to
the IDLE state after calibration.
Solid “
P
”
Program Unit capacity/size (Unit
Code)
d
d
After “P” is selected (by releasing the push button), the IFC
flashes the letter 'P' on the LED. If the push button is pressed
again, the IFC starts to display a single character that corre-
sponds to each different Furnace model size (see Table 10).
Each character displays for three seconds. When the desired
model (character) displays, release the push button. The
selected model (character) flashes for 10 seconds and during
that time the push button must be pressed and held for 5 sec-
onds. Once the IFC accepts the new setting it stores that data
in non-volatile memory and the IFC resets itself. If 10 seconds
expires or the push button is held for less than 5 seconds, the
IFC exits field test mode and proceeds to the IDLE state with-
out programming the unit size.
Table 10. Furnace Model Size Codes
LED Code
Furnace Model Size
1
70,000 BTU with 1/2 HP motor
2
90,000 BTU with 1/2 HP motor
3
90,000 BTU with 3/4 HP motor
4
90,000 BTU with 1 HP motor
5
110,000 BTU with 1 HP motor
6
135,000 BTU with 1 HP motor
7
70,000 BTU with 1/2 HP motor
8
90,000 BTU with 1/2 HP motor
9
90,000 BTU with 3/4 HP motor
0
90,000 BTU with 1 HP motor
!!
110,000 BTU with 1 HP motor