Johnson Controls G76 Series Installation Sheets Manual page 14

Is 24 VAC
available at
Start
transformer?
Is power
Determine why
No
available
voltage is not
to primary?
present
Replace the
transformer
No
Correct
No
Replace
No
Replace
G76x control
Figure 8: No Spark, and System Does Not Work
14 G—G76x Direct Spark Ignition Controls Technical Bulletin
Yes
No
No
Yes
Close
contacts
Turn off supply voltage.
Is high voltage cable
securely attached to
spark transformer?
Yes
Is condition
of high voltage
cable good (not
brittle, burnt,
or cracked?)
Yes
Is spark electrode
ceramic cracked or
is electrode
grounded out?
Is 24 VAC
present from Yes
Terminal THS 2
to ground?
No
Are thermostat
contacts and limit
control contacts
closed?
Yes
Control in
Check continuity of
recycle mode
wiring to determine
why voltage does
not exist at THS 2
Open thermostat
contacts for 30 seconds.
Close contacts and wait
No
for prepurge (if applicable)
period. Is spark
present now?
System was in lockout.
Observe a complete
operating cycle to
determine why control
locked out.
Yes
Replace electrode assembly
End
Is jumper
Yes
installed from
Terminal 5 to
ground?
No
Install
jumper
Is control a
G765 or G766?
Yes
Is LED
Yes
Flashing?
No
Yes
No