Indoor Fireplace User Manual
15
NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
BURNER ADJUSTMENTS 
(QUALIFIED TECHNICIANS ONLY)
Flame Appearance and Sooting
Proper flame appearance is a flame which is 
blue at the base and becomes yellowish-orange 
in the body of the flame. 
When the appliance is first lit, the entire flame 
may be blue and will gradually turn yellowish-
orange during the first 15 minutes of operation. 
If the flame remains  blue, or  if the flame is 
orange with evidence of sooting (black tip), the 
air shutter opening may need to be adjusted.
If  the  air  shutter  opening  is  closed  too  far, 
sooting may develop. Sooting is indicated by 
black puffs developing at the tips of very long 
orange flames.  Sooting results in black deposits 
forming on the logs, appliance inside surfaces 
and on exterior surfaces adjacent to the vent 
termination. 
Sooting is caused by incomplete combustion 
in the flames and lack of combustion air enter-
ing the air shutter opening. To achieve a warm 
yellowish-orange flame with an orange body 
that does not soot, the shutter opening must be 
adjusted between these two extremes. 
Air Shutter Adjustment Guidelines:
Amount of 
Primary Air
Flame 
Color
Air Shutter 
Adjustment
If air shutter is 
closed too far
Flame will 
be orange
Air shutter 
gap should be 
increased
If air shutter is 
open too far
Flame will 
be blue
Air shutter 
gap should be 
decreased
Vermiculite
Figure 13 - Burner Flame Appearance 
Air Shutter Adjustment Guidelines
• If there is smoke or soot present, rst
check the log set positioning to ensure that 
the flames are not impinging on any of the 
logs.  If the log set is properly positioned 
and a sooting condition still exists, then the 
air shutter opening should be increased.
• Themoreoffsetsintheventsystem,thelarger
the air shutter opening will need to be.
• Anapplianceoperatedwiththeairshutter
opened too far, may have flames that appear 
blue and transparent.  These weak, blue and 
transparent flames are termed anemic. 
• Propanemodelsmayexhibitameswhich
candle or appear stringy. If this is present 
and persists, adjust the air shutter to a more 
closed position, then operate the appliance 
for a few more minutes to ensure that the 
flame  normalizes  and  the  flames  do  not 
appear sooty. 
The following chart is provided to aid you in 
achieving  the  correct  air  shutter  adjustment 
for your installation.










