International comfort products C9MVX Installation Instructions Manual page 48

Heating Request with Gas Shut Off:
24 VAC signal applied to W1 terminal of FCB.
The FCB will attempt 4 cycles for ignition then go to soft lockout for 3 hours, and then try for ignition again as long as the heat call
remains. Power reset will clear lockout.
•
Inducer motor turns on at high speed.
•
Following a 15 second prepurge delay, the ignitor begins warm up.
•
The ignitor glows red−hot for 22 seconds, then turns off. The FCB flashes error code 6.
•
The ignitor stays off for 17 seconds, then begins to warm up again.
•
The ignitor glows red hot for 22 seconds then turns off. The FCB continues flashing error code 6.
•
The ignitor stays off for 17 seconds, then begins to warm up again.
•
The ignitor glows red hot for 22 seconds then turns off. The FCB continues flashing error code 6.
•
The ignitor stays off for 17 seconds, then begins to warm up again.
•
The ignitor glows red hot for 22 seconds then turns off. The FCB proceeds to soft lockout. Stops flashing
error code 6, and begins flashing error code 6 + 1.
· The inducer motor de−energizes after a 15 second post purge.
Furnace Control Board Diagnostic Codes (See Figure 49):
OFF = 24VAC or 115VAC is off, fuse is open
Heartbeat = Normal operation or no previous Diagnostic Code
ON SOLID = Soft Lockout − Furnace Control Error (1 hr delay)
If code repeats immediately following power reset then replace control
1 Flash = Not used
2 Flashes = Pressure switch(es) closed when should be open
3 Flashes = Low pressure switch open when should be closed
4 Flashes = Limit or flame roll−out switch open (less than 2 minutes)
5 Flashes = Flame sensed out of sequence
6 Flashes = Failure to ignite or flame sense lost while running
6 + 1 Flashes = Soft Lockout − Max of four trials for ignition reached (3hr delay)
7 Flashes = Soft Lockout − Limit or flame roll−out switch open longer than 2 minutes (1 hr delay)
(roll−out switch requires manual reset)
8 Flashes = Permanent Lockout − Gas valve relay contact stuck closed or miswired gas valve (power reset only)
9 Flashes = High pressure switch open when should be closed
10 Flashes = Line voltage polarity or improper transformer phasing on twinned applications
NOTE: The 6 + 1 designation indicates a combination of flash
codes.
* If status code recall is needed, briefly (2−3 seconds) remove then
reconnect one limit switch wire (main or rollout) to display last
stored status code. Do not remove power or blower door before
initiating status code recall or code will be lost. Code is
automatically cleared after 72 hours or upon power reset.
* Proper flame sense microamps: 0.7 microamps D.C. minimum,
2.0 − 4.0 microamps nominal
HUMIDIFIER − The 24VAC HUM is energized when the low pressure switch closes on a call for heat. The 115V HUM (called HUM on
Control) is energized when the inducer is energized.
ELECTRONIC AIR CLEANER − EAC is energized when there is a blower speed call. It is NOT energized when blower operates in the
hard−wired continuous fan mode.
48
Figure 49
DIP Switch
See "Wiring
Diagram"
for switch settings
24 VAC
HUM
25−24−74
Specifications are subject to change without notice.
Control Board
FUSE
DEHUM
Diagnostic Light
115
VAC
HUM
EAC
440 01 2024 04