STEP
ACTION
YES
NO
GO TO
13
Is outdoor condensing unit operating during heating cycle?
16
14
14
Check temperature rise and external static pressure with
blower access panel in place. Temperature rise should be
mid range or higher than midpoint of range stated on fur-
nace rating plate. External static pressure must not exceed
.7 in.w.c. If return temperature is below 60 degrees F, con-
densation may form on heat exchangers. If left uncorrected,
failure will result.
15
15
Check return air ducts in unheated spaces for leaks.
9
16
Fix problem.
9
Status Code 11
NO PREVIOUS CODE – Stored status codes are erased after 72 hours or can be cleared by jumpering R, W/W1, and Y/Y2 thermostat leads
while setup switch SW1-1 is ON. Run system through a heating or cooling cycle to check system.
This usually indicates one of the following:
•
The status history has been cleared and setup switch SW1-1 is in the ON position.
•
Component test was successfully completed and setup switch SW1-6 is in the ON position.
STEP
ACTION
YES
NO
GO TO
1
Remove the blower access panel, depress the door switch.
Use piece of tape to hold it closed.
2
2
Is setup switch SW1-1 in the ON position.
3
5
3
Put setup switch SW1-1 in the OFF position.
4
4
Go to the page number indicated in Index for the CLEANUP
AND STARTUP INSTRUCTIONS.
INDEX
5
Is setup switch SW1-6 in the ON position.
6
7
6
Put setup switch SW1-6 in the OFF position.
4
7
Jiggle setup switches SW1-1 and SW1-6 back and forth. If
status code 11 continues to flash replace the variable
speed furnace control
4
Status Code 12
BLOWER ON AFTER POWER UP - Blower will run for 90 seconds when furnace power is interrupted and later restored during a call for
heat (R-W/W1 closed) or if the call for heat is interrupted (R-W/W1 opens) during the blower on-delay period. If this status code repeats every
couple of minutes it is probably caused by a direct short in the pressure switch circuits, gas valve GV, wiring to gas valve GV, or humidifier
coil.
STEP
ACTION
YES
NO
GO TO
1
Remove the blower access panel and disconnect the W/W1
thermostat lead from the variable speed furnace control.
2
2
Depress the door switch. Use piece of tape to hold it
closed.
3
3
Set thermostat to call for heat and set the thermostat fan
control to AUTO position if equipped. Then reconnect the
W/W1 thermostat lead to the variable speed furnace con-
trol.
4
4
Does the furnace keep repeating the following cycle?
Induced draft motor IDM runs, induced draft motor IDM
stops, blower motor BLWM runs for 90 seconds while AM-
BER LED status light flashes status code 12.
5
20
5
Do you have less than 17-vac across R and C
OM
-24V on
the variable speed furnace control?
6
14
6
Do you have less than 90-vac across L1 and NEUTRAL-L2
on the variable speed furnace control?
7
10
7
Make sure wire gage between main fuse box and furnace
complies with wire size specification in Installation, Start-Up,
and Operating Instructions.
8
8
Fix problem.
9
9
Go to the page number indicated in Index for the CLEANUP
AND STARTUP INSTRUCTIONS.
INDEX
10
Disconnect the R thermostat lead.
11
11
Do you have less than 19-vac across R and C
OM
-24V on
the variable speed furnace control?
12
13
12
Replace transformer.
9
14
