Monessen Hearth Magnum Unvented Vent-Free Fireboxes MCUF42D SERIES - Manual (Page 17)

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17
USING OPTIONAL AK-4 OUTSIDE AIR KIT
The use of outside air for combustion is optional unless required by building codes. It is only necessary to supply outside
combustion air to one side of the fi replace. Use the model AK4 combustion air kit.
MODEL AK-4 COMBUSTION AIR ASSEMBLY
1. Remove the cover plate from the 4" outlet opening location on the left or
right outside of the fi replace.
2. Place the insulation ring between the AK-4 starting collar and fire-
place wall.
3. Place the starting collar (4") into the hole on the side of fi replace. Fasten it in place with the four sheet metal screws
provided. See Figures 21 and 22.
Note: The air starting collar extends through the fi replace outer wrap. When the air starting collar is
securely attached, it will form a seal against the fi replace wall.
4. Attach outside duct to starting collar with duct clamp or screws. See Figure 22.
DO NOT remove the
cover if the outside air
will not be connected.
W
ARNING
Figure 21 - Attaching Outside Air Starting Collar
and Insulation Ring to Left Side of Fireplace
Figure 22- Attaching Outside Duct
to Starting Collar
Insulation Ring
AK-4 Starting
Collar
Sheet
Meal
Screws
Left Side of
Fireplace
Shorter End
of Air Starting
Collar
Air Starting
Collar
Duct
Screws
Left Side of
Fireplace
5. Cut a 6-inch diameter opening for model AK-4 in the outside
wall covering where the outside vent is to be located. See
Figure 23.
6. Select and cut a piece of duct long enough to attach to the
fi replace and stick out at least 3" beyond the face of the wall
to which the AK-4 inlet air vent will be attached. See Figure
22.
Figure 23 - Combustion Air Assembly for
Model No. AK-4
Nail
Holes
Use FP-4 U duct for maximum effi ciency
and safety. Do not use a combustible
duct. Always use UL Listed Class 0 or
1 duct material.
W
ARNING
6" Diameter
Hole
Duct
Extending
3"min.
AK-4 Inlet
Air Vent
Screw
Screws
Continued