Vulcan-Hart MHB24G Electric Steamer User Manual


 
VHX SERIES STEAMER - TROUBLESHOOTING
SYMPTOM POSSIBLE CAUSES
F24700 (October 2001)
Page 62 of 68
Blower operating, no pilot gas flow. 1. Main gas supply turned OFF.
2. Ignition module lockout. Turn power switch OFF for several
seconds then ON to reset the module.
3. Air pressure switch:
A. Not mounted in true vertical position.
B. Incorrect pressure setting.
C. Malfunctioning switch.
4. Malfunctioning Ignition module.
5. Malfunctioning pilot gas valve.
6. Blocked or dirty pilot gas orifice.
Pilot flame not proving or lighting main
burner.
1. Gas not ON.
2. Incorrect manifold pressure for pilot gas.
3. Poor connection between igniter and ignition cable.
4. Fouled spark igniter.
5. Incorrect gap in spark igniter.
6. Faulty igniter or cracked insulation.
7. Improper ground.
8. Low water level in boiler or boiler not filling.
9. Flame sensing current too low.
10. Cracked or incorrect burner head attachment.
11. Incorrect igniter positioning.
12. Incorrect pilot orifice.
Main burner not lighting correctly or
excessive ignition noise.
1. Blocked or dirty air orifice on blower.
2. Insufficient gas supply pressure.
3. Incorrect gas pilot pressure.
4. Incorrect gas manifold pressure.
5. Pilot flame not sensing correctly.
6. Burner tube insulation broken or deteriorated.
7. Blocked or restricted flue.
8. Incorrect pilot or main gas burner orifice size.
Excess combustion noise or combustion
induced harmonics.
1. Blocked or dirty air orifice on blower.
2. Incorrect gas manifold pressure.
3. Insufficient gas supply pressure.
4. Steam vapors introduced into blower inlet.
5. Loose flue connections.
Boiler not maintaining set pressure
and/or excessive burner on time.
1. Leaking boiler blowdown valve.
2. Manual blowdown valve on water level probe housing open.
3. Malfunctioning 13 psi overshoot relief valve.
4. Low incoming gas supply pressure.
5. Excessive load on steam outlet.