Install Instructions

20
Honeywell Electronic Ignition Troubleshooting Guide
Figure 18: Troubleshooting Guide
"CALL FOR HEAT."
POWER TO
MODULE? (24 V
NOMINAL)
NO
YES
30 SECOND
PREPURGE
DELAY?(S8670
ONLY)
YES
SPARK
ACROSS IGNITOR/
SENSOR
GAP?
YES
NO
CHECK LINE VOLTAGE POWER, LOW VOLTAGE TRANSFORMER, LIMIT CONTROLLER, THERMOSTAT (CONTROLLER), AND WIRING. ALSO,
CHECK AIR PROVING SWITCH ON COMBUSTION AIR BLOWER SYSTEM (IF USED) AND THAT THE VENT DAMPER END SWITCH (IF USED)
IS MADE.
REPLACE S8670
PULL IGNITION LEAD AND
CHECK SPARK AT MODULE.
SPARK OK? NO
YES
CHECK IGNITION CABLE, GROUND WIRING, CERAMIC INSULATOR, AND SPARK GAP AND CORRECT.
CHECK BOOT OF THE IGNITION CABLE FOR SIGNS OF MELTING OR BUCKLING. TAKE PROTECTIVE ACTION TO SHIELD CABLE
AND BOOT FROM EXCESSIVE TEMPERATURES.
REPLACE MODULE
NO
TURN GAS SUPPLY ON AND
RECYCLE "CALL FOR HEAT."
PILOT BURNER
LIGHTS?
YES
NO
SPARK
STOPS WHEN
PILOT IS
LIT?
YES
NO
MAIN BURNER
LIGHTS?
YES
NO
SYSTEM
RUNS UNTIL "CALL
FOR HEAT"
ENDS?
YES
NO
CHECK THAT ALL MANUAL GAS VALVES ARE OPEN, SUPPLY TUBING AND PRESSURES ARE GOOD, AND PILOT BURNER
ORIFICE IS NOT BLOCKED (PILOT GAS FLOWING).
CHECK ELECTRICAL CONNECTIONS BETWEEN MODULE AND PILOT OPERATOR ON GAS CONTROL.
CHECK FOR 24 VAC ACROSS PV-MV/PV TERMINALS ON MODULE, IF VOLTAGE IS OK, REPLACE GAS CONTROL. IF NOT,
REPLACE MODULE.
NOTE: IT MAY BE NECESSARY TO RECYCLE THE "CALL FOR HEAT" MORE THAN
ONCE TO CLEAR THE PILOT SUPPLY TUBES OF AIR.
NOTE: IF CONTROL GOES INTO LOCKOUT OR RETRY DELAY, RESET THE "CALL FOR HEAT."
CHECK CONTINUITY OF IGNITION CABLE AND GROUND WIRE.
CLEAN FLAME ROD.
CHECK ELECTRICAL CONNECTIONS BETWEEN FLAME ROD AND MODULE.
CHECK FOR CRACKED CERAMIC FLAME ROD INSULATOR.
CHECK THAT PILOT FLAME COVERS FLAME ROD AND IS STEADY AND BLUE.
ADJUST PILOT FLAME.
IF PROBLEM PERSISTS, REPLACE MODULE.
CHECK FOR 24 VAC ACROSS PV-MV/PV TERMINALS ON MODULE. IF NO VOLTAGE, REPLACE MODULE.
CHECK ELECTRICAL CONNECTIONS BETWEEN MODULE AND GAS CONTROL INCLUDING SAFETY CONTROLS WIRED IN THE CIRCUIT. IF
OKAY, REPLACE GAS CONTROL.
NOTE: IF CONTROL GOES INTO LOCKOUT OR RETRY DELAY, RESET THE "CALL FOR HEAT."
CHECK CONTINUITY OF IGNITION CABLE AND GROUND WIRE.
NOTE: IF GROUND IS POOR OR ERRATIC, SHUTDOWNS MAY OCCUR OCCASIONALLY EVEN THOUGH OPERATION IS NORMAL
AT THE TIME OF CHECKOUT.
CHECK THAT PILOT FLAME COVERS FLAME ROD AND IS STEADY AND BLUE. PILOT FLAME MUST NOT BE MOVING AROUND DUE TO
OUTSIDE AIR FLOWS, ETC.
ADJUST PILOT FLAM
E. CHECK GAS PRESSURE MEETS APPLIANCE SPECIFICATIONS WHILE APPLIANCE MAIN BURNER IS ON AND ALL
OTHER GAS APPLIANCES ON THE SUPPLY ARE OPERATING AT FULL RATE.
IF CHECKS ARE OKAY, REPLACE MODULE.
"CALL FOR HEAT" ENDS
SYSTEM
SHUTS OFF?
NO
CHECK FOR PROPER THERMOSTAT (CONTROLLER) OPERATION.
REMOVE MV LEAD AT MODULE. IF VALVE CLOSES, RECHECK TEMPERATURE CONTROLLER AND WIRING. IF NOT, REPLACE
GAS CONTROL.
VII. System Start-up (continued)