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NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
Innovative Hearth Products
Montebello
®
ST Direct-Vent Gas Fireplaces
Operation Instructions
900355-00, 06/2016
Figure 83
Volcanic Stone
Burner Flame Appearance
(Control Side)
BURNER ADJUSTMENTS
(QUALIFIED TECHNICIANS ONLY)
Flame Appearance and Sooting
Proper flame appearance is a flame that 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
30 minutes of operation. After 30 minutes of
operation, if the flame is 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.
Burner Air Shutter Adjustment
Guidelines
• If there is smoke or soot present, first 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.
• The more offsets in the vent system, the larger
the air shutter opening will need to be.
• An appliance operated with the air shutter
opened too far, may have flames that appear
blue and transparent. These weak, blue and
transparent flames are termed anemic.
• Propane models may exhibit flames which
candle or appear stringy. If this is present
and persists, adjust the air shutter to a more
OPEN 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.
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
Figure 84
Volcanic Stone
Burner Flame Appearance
(Opposite Control Side)
Air Shutter Adjustment Lever
