SYMPTOM
POSSIBLE CAUSES
Burner won’t light.
Gas not on.
Ignition control module reset switch in the OFF position
or malfunctioning.
Ignition module not receiving power. Check ignition
module transformer for 24VAC output to module on
automatic ignition systems.
Unit not properly grounded and/or polarity of incoming
power is incorrect on automatic ignition systems.
Low incoming gas pressure. See Manifold Pressure
Adjustment.
Ignition module malfunction.
Gas combination control valve malfunction.
Boiler not filling. Check fill solenoid for power, clogging or
malfunction.
Water level control malfunction.
Water too ”pure” for probes to properly conduct
electricity.
High limit thermostat open (if equipped).
High limit pressure switch open.
Cycling pressure switch open or set too high. Unit is
cycling on high limit. See PRESSURE SWITCHES .
Burner won’t stay lit.
Gas pressure low. See Manifold Pressure Adjustment.
Ignition module malfunction.
Check gas orifice for obstruction.
Pilot not lit or goes out.
Gas not on.
Low incoming gas pressure.
Check thermopile millivolts.
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.
Pilot not adjusted correctly. See Pilot, Thermocouple,
Gas Combination Control Valve, Main Burners.
Burners ignite too violently. Check gas pressure to the
unit. See Manifold Pressure Adjustment”.
If auto ignition and no sparking - ignition module
malfunction.
Wrong pilot assembly used.
Spark Ignitor not sparking.
Incorrect spark gap setting. See Automatic Ignition
Systems.
Poor ground between pilot bracket and burner.
Loose, broken or damaged lead wires (including ground)
from ignition module to ignitor.
Ignitor boot on ignition cable loose, damaged or missing
causing excessive ignition voltage leakage.
VSX BOILER BASE SERIES CONVECTION STEAMERS - TROUBLESHOOTING
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