12
NOTE: DIAGRAMS & ILLUSTRATIONS ARE NOT TO SCALE.
Installation of Vent Restrictor
A vent restrictor may be needed with this
appliance. The restrictor is installed in the
appliance top flue outlet as shown in Figure
16, either before adding vent, from above, or
after installation of vent from below, within the
firebox. The restrictor is self securing through
a positive friction fit.
Determine the venting for the appliance. If the
vent run will include at least 8 feet of vertical
rise, then install the restrictor in the appliance
collar before connecting any vent (Refer to
Figure 16). Place the restrictor inside the ap-
pliance vent collar and press in place.
Note: The restrictor is included within the
firebox.
Step 3. INSTALL THE VENT SYSTEM
General InformationThese instructions should be used as a
guideline and do not supersede local codes
in any way. Install venting according to local
codes, these instructions, the current National
Fuel Gas Code (ANSI-Z223.1) in the USA or
the current standards of CAN/CSA-B149.1
in Canada.
Ensure clearances are in accordance with
local installation codes and the requirements
of the gas supplier.
Dégagement conforme aux codes
d'installation locaux et aux exigences du
foumisseunde gaz.
Use only approved venting components. See Approved Vent Components on Page 2.These fireplaces must be vented directly to the outside.The vent sy stem may not service multiple
appliances, and must never be connected to a
flue serving a solid fuel burning appliance. The
vent pipe is tested to be run inside an enclosed
wall (such as a chase). There is no requirement
for inspection openings in the enclosing wall at
any of the joints in the vent pipe.
Figure 16Vent Restrictor Installation
(Top Vent)
A vent restrictor may be needed when vertical-
ly terminating the vent system above the roof
(when using the appliance top vent), install
vent restrictor in the top vent of the fireplace
outlet on all MLDVT series models. If needed,
install the restrictor orientated as shown,
either from inside or outside the unit,in the
inner fireplace collar.
Appliance Top
Vent Outlet
Restrictor
Inner
Fireplace
Collar
Select Venting System - Horizontal or Vertical
With the appliance secured in framing, determine
vent routing and identify the exterior termina-
tion location. The following sections describe
vertical (roof) and horizontal (exterior wall)
vent applications. Refer to the section relating
to your installation. A list of approved venting
components are shown on Pages 35 and 36.
LENNOX HEARTH PRODUCTS • MERIT® SERIES DIRECT-VENT GAS FIREPLACES • MODELS MLDVT-30/35/40/45 • INSTALLATION INSTRUCTIONS