Vulcan-Hart VSX Series Service Manual page 80

SYMPTOM
Burner won't light.
Burner won't stay lit.
Pilot not lit or goes out.
Spark Ignitor not sparking.
Form 24627 (December 98)
VSX SERIES STEAMER - TROUBLESHOOTING
GAS MODELS ONLY
1. Gas not on.
2. Ignition control module reset switch in the OFF position or
malfunctioning.
3. Ignition module not receiving power. Check ignition module
transformer for 24VAC output to module on automatic ignition
systems.
4. Unit not properly grounded and/or polarity of incoming power is
incorrect on automatic ignition systems.
5. Low incoming gas pressure. See "MANIFOLD PRESSURE
ADJUSTMENT" in "SERVICE PROCEDURES".
6. Ignition module malfunction.
7. Gas combination control valve malfunction.
8. Boiler not filling. Check fill solenoid for power, clogging or
malfunction.
9. Water level control malfunction.
10. Water too "pure" for probes to properly conduct electricity.
11. High limit thermostat open (if equipped).
12. High limit pressure switch open.
13. Cycling pressure switch open or set too high. Unit is cycling on
high limit. See "PRESSURE SWITCHES (GAS AND ELECTRIC
MODELS) in SERVICE PROCEDURES".
1. Gas pressure low. See "MANIFOLD PRESSURE ADJUSTMENT"
in "SERVICE PROCEDURES".
2. Ignition module malfunction.
3. Check gas orifice for obstruction.
1. Gas not on.
2. Low incoming gas pressure.
3. Check thermopile millivolts.
4. Pilot going out due to drafts, excess steam from drain or unit not
level. Improper venting can direct the pilot flame away from
thermopile or flame sensor.
5. Pilot not adjusted correctly. See "PILOT, THERMOCOUPLE OR
MAIN BURNERS" in "SERVICE PROCEDURES".
6. Burners ignite too violently. Check gas pressure to the unit. See
"MANIFOLD PRESSURE ADJUSTMENT" in "SERVICE
PROCEDURES".
7. If auto ignition and no sparking - ignition module malfunction.
8. Wrong pilot assembly used.
1. Incorrect spark gap setting. See "AUTOMATIC IGNITION
SYSTEMS" in "SERVICE PROCEDURES".
2. Poor ground between pilot bracket and burner.
3. Loose, broken or damaged lead wires (including ground) from
ignition module to ignitor.
4. Ignitor boot on ignition cable loose, damaged or missing causing
excessive ignition voltage leakage.
5. Ceramic flame rod insulator on ignitor cracked or damaged from
extreme heat.
6. Ignition module not receiving power.
7. Ignition module malfunction.
POSSIBLE CAUSES
Printed in U.S.A.