16
NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
Ref. Air shutter Patent:
U.S. Pat. 5,553,603
Adjustment Rod Positions
(when viewed from above)

Figure 16

Main Burner Factory Air Shutter
Opening Setting - All Models
Model Natural
Gas
Propane
Gas
MPB35ST
1/8”
3.2mm
1/4”
6.4mm
Increase Shutter Opening
In This Direction
Decrease Shutter Opening
In This Direction Note - Burners are
omitted in this
view for clarity.
Orifice
Air Shutter
Adjusting
Rod
1. Locate adjustment rod and adjust air shutter
to the standard setting as shown in Figure
16 (adjustment rod is located in the lower
control area). Note: Rotating the adjustment
rod count erclockwise decreases air and
clockwise increases air.
2. Light appliance (follow lighting procedure on
lighting label in control compartment or see
care and operation instructions 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 (see Figure 15). If the
following conditions are present, adjust
accordingly.
• If ame appears weak or sooty, adjust
the air shutter, incrementally, to a more
open position until the proper flame
appearance is achieved.
• If ame 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 and the burner OFF/ON switch
OFF (and remote switches, if applicable).
5. When satisfied that the burner flame appear-
ance is normal, close the lower control
compartment door.

Burner Air Shutter Adjustment Procedure

WARNINGS• Air shutter adjustment should only be performed by a quali-fied professional ser vice technician.• Ensure front glass panel are in place and sealed during adjustment. CAUTIONS
• 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.
Electronic Appliance Checkout
To light the burner, refer to the lighting instruc-
tions on Page 24. Ensure the igniter lights the
pilot. The pilot flame should engulf the flame
sensor as shown in Figure 18.
Figure 18 - Electronic Pilot Assembly
3/8" to 1/2"
(9 -13 mm)
Ground
Electrode
Flame Rod
Hot Surface
Igniter
Proper Flame
Adjustment
Pilot
Nozzels
Proper Pilot Flame Appearance
Figure 17 - Millivolt Pilot Assembly
Proper Pilot Flame
Appearance
Thermocouple
Thermopile
Pilot
Nozzels
3/8" Min.
(9 mm)
Igniter Rod
Hood
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" min (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 17.
To light the burner, refer to the lighting instruc-
tions on Page 22.