16
APPEARANCE
CAUSE
SMALL BLUE FLAME
Check for lack of gas from:
• Clogged orifice filter
• Clogged pilot filter
• Low gas supply pressure
• Pilot adjustment at minimum
LAZY YELLOW FLAME
Check for lack of air from:
• Large orifice
• Dirty lint screen, if used
• Dirty primary air opening, if there is one
• Pilot adjustment at minimum
WAVING BLUE FLAME
Check for :
• Excessive draft at pilot locations
• Recirculating products of combustion
NOISY LIFTING BLOWING FLAME
Check for:
• High gas pressure
HARD SHARP FLAME
This flame is characteristic of manufactured gas
Check for:
• High gas pressure
• Orifice too small