Lennox Hearth MERIT PLUS MP-36OD - Manual (Page 8)

NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE. 8
Figure 16
Air Duct
Air Inlet
Clamps
Note: Air Inlet
Must Be Free Of
Any Obstructions
Install as follows:
Connect the 4" (102 mm) Class 0 air duct
provided, to the collar on the fi replace with the
clamps provided in the kit’s hardware package
(Figure 16).
Route the Class 0 metallic air duct out the back
wall or side wall, up through the ceiling or fl oor
joists to an outside wall. The air duct’s inlet
should be located above any anticipated
snow level. Check local building codes for any
restrictions. We recommend that the inlet be
at least 4 feet above grade level.
Note: Air inlet ducts must not terminate in
attic space.
Figure 17
3 Feet
Duct Hole Framing:
Cut or frame a hole through the outside of
the enclosure for the installation of the duct
inlet hood. A 5" (127 mm) diameter hole is
required. Feed the loose end of the fl exible
duct through the hole cut for the inlet hood and
attach to the collar on the inlet hood using two
(2) screws. Insert the hood into the opening.
Secure in place with nails driven through the
holes in hood fl ange. Seal with noncombustible
waterproof silicon type caulking. If additional
duct is needed, use Class 0 metallic air duct
(refer to Figure 16).
Outside Air Kit (provided)
Required on all Outdoor installations
Optional on Indoor installations
Outside Air Kit Installation (provided)
These appliances are equipped with a com-
bustion air inlet collar so that it is possible to
duct combustion air from the outdoors to the
fi rebox. To accomplish an outside air hook-
up, use only the Outside Air Kit provided with
these appliances. These kits come complete
with all components necessary in completing
a combustion air vent system.
Indoor Installations - An Air Gate Kit must be
installed prior to the installation of the Outside
Air Kit (purchased separately - see Page 23 for
ordering information).
Outdoor Installations - Units installed outdoors
are required to have the Outside Air Kit (pro-
vided) installed without the Air Gate Kit. The
optional Air Gate Kit is not approved on outdoor
installations.
Note: Secure the duct hood to a vertical post
with the inlet positioned downward. Ensure that
nothing blocks the hood opening. This duct
must never terminate higher than 3 feet below
the fi replace termination (Figure 17).
Air Inlet
(duct hood)
CAUTION
Avoid installing the air inlet
where the opening could be
blocked by snow, bushes or
other obstacles. The maximum
height for the outside air is 50
feet above the hearth, provid-
ing the air inlet is terminated a
minimum of three (3) feet below
the chimney cap level.
ATTENTION
Évitez d’installer la prise d’air ou
l’ouverture pourrait etre bloquee
par la neige, les buissons ou
d’autres obstacles. La hauteur
maximum pour la prise d’air est
de 50 pi. Au dessus de la base du
foyer à condition qu’elle se situe
à au moins 3 pi. En dessous de
la sortie de la cheminée.