American Standard UHMB060ACV3VB Series Service Facts page 48

Service Facts
DEFINITION:
TRIAC ERR – The triac reduces voltage
applied to the ignitor. A voltage error has
been sensed
IGNITOR ERR – The control board has
sensed that the ignitor circuit is open or
shorted.
The Ignition system is very dependent on
good earth ground connections. A poor earth
ground can result in multiple ignitor and/or
triac failures.
AC VOLTS HI – The control board has
sensed that the applied voltage to the ignitor
has exceeded it's limit
AC VOLTS LOW – 98 vac nominal
Replace ignitor.
Check operation
Replace the IFC.
Check operation
NO
48
6 Flash Fault LED
Scroll through
User Interface to
View number 1 of
Last 4 Faults
User Interface
shows a TRIAC
ERR, IGNITOR
ERR, or AC VOLTS
Disconnect
electrical power to
the furnace
Disconnect ignitor
and check
resistance of
Is resistance
Verify all ground
NO reading between
connections
37 – 70 ohms?
Verify all ground
connections.
Check Triac
Check ignitor for YES
Is it damaged?
wire insulation
damage.
Check all wiring for
insulation damage
and connection
Is there wiring
or insulation
damage?
Repair or replace
wiring. Check
operation
HI?
ignitor
YES
NO
integrity
YES
Damaged Triac
Good Triac
UHM-DHM-SF-1V-EN