Burner Flame Adjustments; Millivolt Appliance Checkout; Electronic Appliance Checkout - Lennox Merit MLDVTCD-35NM Care And Operation Instructions Manual

LENNOX HEARTH PRODUCTS • MERIT
Burner Air Shutter Adjustment Procedure
WARNING
• Air shutter adjustment should
only be performed by a quali-
fied professional service
technician.
• Ensure front glass panel are
in place and sealed during
adjustment.
CAUTION
• Soot will be produced if the
air shutter is closed too much.
Any damage due to carboning
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. Locate adjustment rod and adjust air shutter
to the standard setting as shown in Figure
8 (adjustment rod is located in the lower
control compartment).
NOTE: Rotating the adjustment rod down
to decrease air and up to increase air.
2. Light appliance (follow lighting procedure on
lighting label in control compartment or see
the lighting instructions, Pages 20 - 23 in
this manual).
3. Allow the burner to operate for at least 15 min-
utes while observing the flame continuously
to ensure that the proper flame appearance
has been achieved (Figure 7). 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 stays lowered blue, adjust the air
shutter, incrementally, to a more closed
position until the proper flame appearance
is achieved.
4. Leave the control knob (off/pilot/on) in the
ON position (millivolt models) and the burner
OFF/ON switch OFF (and remote switches,
if applicable).
5. When satisfied that the burner flame ap-
pearance is normal, close the lower control
compartment door (Figure 7 on Page 14).
SERIES DIRECT-VENT CONTEMPORARY DESIGN GAS FIREPLACES • MODEL MLDVTCD-35 • CARE AND OPERATION
®
Burner
Tube
Air Shutter
Adjustment Rod Down
(fully open air opening
position)
Main Burner Factory Air Shutter
Opening Setting
Natural
Model
MLDVTCD-35 Closed
Figure 8 - Burner Air Shutter
Adjustment

Millivolt Appliance Checkout

The pilot flame should be steady, not lifting
or floating. Flame should be blue in color with
traces of orange at the outer edge.
The top 3/8" (10 mm) at the pilot generator
(thermopile) and the top 1/8" minimum (tip)
of the quick drop out thermocouple should be
engulfed in the pilot flame. The flame should
project 1" (25 mm) beyond the hood at all three
ports (see Figure 9).
To light the burner, refer to the lighting instruc-
tions on Page 20.
NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
Adjustment Set-Screw
Adjustment
Rod Up
(closed min.
position)
Propane
Gas Gas

Electronic Appliance Checkout

Expose half of
the hole
To light the burner, refer to the lighting instruc-
tions on Page 22. Ensure the igniter lights the
pilot. The pilot flame should engulf the flame
sensor as shown in Figure 10.
Igniter Rod
Pilot Hood
Thermocouple
Pilot
Nozzels
Thermopile
Figure 9 - Millivolt Pilot
Igniter
Flame Rod
(Sensor)
Figure 10 - Electronic Pilot
3/8" Min.
(9 mm)
Pilot
Hood
15