Step 10. Adjust Burner - Lennox MERIT Series Installation Instructions Manual

LENNOX MERIT

Step 10. Adjust burner

The following paragraphs address adjustment
concerns and procedures.
Flame Appearance and Sooting
Proper flame appearance is a matter of taste.
Generally most people prefer the warm glow of
a yellow to orange flame. Appliances operated
with air shutter openings that are too large, or
with long vertical vent runs, will exhibit flames
that are blue and transparent. These weak, blue
and transparent flames are termed anemic.
If the air shutter opening is too small 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. Soot-
ing is caused by incomplete combustion in the
flames and a lack of combustion air entering
the air shutter opening.
To achieve a warm yellow to orange flame with
an orange body that does not soot, the shutter
opening must be adjusted between these two
extremes.
No smoke or soot should be present. Reposition
the log set if the flames impinge on any of them.
If sooting conditions exist, the air shutter
opening on the main burner can be adjusted.
Normally, the more offsets in the vent system,
the greater the need for the air shutter to be
opened further.
SERIES B-VENT GAS FIREPLACES • 36" LMBV MODELS • INSTALLATION INSTRUCTIONS
®
WARNING: AIR SHUTTeR AdjUSTmeNT
SHOULd ONLY be peRFORmed bY A
QUALIFIed pROFeSSIONAL SeRvICe
TeCHNICIAN.
Adjustment
To adjust the flame, position the air shutter to the
nominal setting (Figure 21 ). Allow the burner
to operate for at least 30 minutes. Observe the
flame continuously. If it appears weak or sooty
as previously described, adjust the air shutter
open or closed until desired effect is achieved.
Note: If the flame still appears anemic
with the air shutter closed all the way
(usually a result of lengthy vertical vent-
ing runs), turn off the appliance, turn off
the gas supply, wait for the parts to cool
and access the air shutter. The shutter is
prevented from actually closing by a tab
that is bent over into the opening. Remove
this obstruction by bending back. Reas-
semble and restart the appliance and after
30 minutes reobserve the flame. Adjust
the air shutter as described.
NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
Nominal Air Shutter Settings
Natural Gas - 1/16" (1.59 mm) Open
Propane Gas - 1/4" (6.35 mm) Open
Figure 21
When satisfied that the appliance operates
properly, proceed to finish the installation.
Leave the control knob/lever in "ON" position
and turn the remote switch "OFF." Replace the
refractory access panel.
11