Lennox Merit MLDVT-35NM-FB Installation Instructions Manual page 30

LENNOX HEARTH PRODUCTS • MERIT
WARNING
• Air shutter adjustment
should only be performed
by a qualified professional
service technician.
• Ensure front glass panel
is in place and sealed
during adjustment.
CAUTION
• Soot will be produced if the
air shutter is closed too much.
Any damage due to sooting,
resulting from improperly
setting the air shutter, is not
covered under the warranty.
• The air shutter door and nearby
appliance surfaces are hot.
Exercise caution to avoid injury
while adjusting flame appearance.
1. Move the adjustment rod down to
decrease air flow and up to increase it.
(rod located in the lower control area).
Position the air shutter to the factory
setting as shown in Table 28.
2. Light the appliance (follow the lighting
procedure on the lighting label in the
control compartment or in the Care and
Operation Instructions).
3. Allow the burner to operate for at least
15 minutes while observing the flame
continuously to ensure that the proper
flame appearance has been achieved
(Figure 37, and Figure 38). If the
following conditions are present, adjust
accordingly.
• If flame appears weak or sooty, adjust
the air shutter, incrementally, to a
more open position until the proper
flame appearance is achieved.
• If flame remains blue, adjust the air
shutter, incrementally, to a more
closed position until the proper
flame appearance is achieved.
Table 27: Air Shutter Adjustment Guidelines
Amount of
Flame Color
Primary Air
If air shutter
Flame will
is closed
be orange
too far
If air shutter
Flame will
is open
be blue
too far
4. When satisfied that the burner flame
appearance is normal, reinstall the
lower control compartment door, then
proceed to finish the installation.
30
SERIES DIRECT-VENT GAS FIREPLACES • MLDVT-30/35/40/45 • INSTALLATION INSTRUCTIONS
®
Figure 37: Burner Flame Appearance, MLDVT-30/35
Figure 38: Burner Flame Appearance, MLDVT-40/45
Table 28: Factory Air Shutter Settings
Models
MLDVT-30/35
Air Shutter
Adjustment
Air shutter
gap should be
MLDVT-40
increased
Air shutter
gap should be
MLDVT-45
decreased
DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
Factory Air
Gas Type
Shutter Setting
Natural Gas Closed
1/16 in.
Propane
(1.574 mm)
Natural Gas Closed
3/32 in.
Propane
(2.362 mm)
Natural Gas Closed
1/8 in.
Propane
(3.175 mm)
Adjustment Set-Screw
Adjustment
Rod Up
(Fully-Open
Burner
Position)
Tube
Air Shutter
Adjustment Rod Down
(Fully-Closed Position)