23
75D2523
MDV Series Direct Vent Gas Fireplace
VentIng InstallatIon
InstallatIon for VertIcal
termInatIon
1. Determine the route your vertical venting will take. If
ceiling joist, roof rafters or other framing will obstruct
the venting system, consider an offset. Refer to
Figure 32
to avoid cutting load bearing members.
note:
Pay special attention to these installation instructions
for required clearances (air space) to combustibles when
passing through ceilings, walls, roofs, enclosures, attic
rafters, etc. Do not pack air spaces with insulation. Also
note maximum vertical rise of the venting system and any
maximum horizontal offset limitations. Offsets must fall
within the parameters shown on
Page 13, Figure 15.
2. Set fireplace in desired location. Drop a line plumb down
from the ceiling to the position of the flue exit. Mark the
center point where the vent will penetrate the ceiling.
Drill a small locating hole a this point.
Drop a plumb line from the inside of the roof to the ceiling
locating hole in the ceiling. Mark the center point where
the vent will penetrate the roof. Drill a small locating hole
at this point.
1
2
3
4
1
2
3
4
FP1179
max bends
Example:
Elbow 1 = 90°
Elbow 2 = 45°
Elbow 3 = 45°
Elbow 4 = 90°
Total Angular = 270°
Variation
FP1179
Figure 31 -
Maximum Elbow Usage
FP1969
offset w/ wallstrap
Figure 32 -
Offset with Wall Strap and 45° Elbows
Roof Flashing
Wall Strap
45° Elbows
Ceiling Firstop
FP1669
flat ceIlIng InstallatIon
1. Cut a 10
Z\x
" (267 mm) square hole in the ceiling using
the locating hole as a center point The opening should
be framed to 10
Z\x
" x 10
Z\x
" (267 x 267 mm) inside dimen-
sions as shown in
Figure 34
using framing lumber the
same size as the ceiling joist. If the area above the
ceiling is an insulated ceiling or a room, nail firestop
from the top side. This prevents loose insulation from
falling into the required clearance space.
Figure 33.
Otherwise, install firestop below the framed hole. The
firestop should be installed with no less than three nails
per side.
Figure 34
2. Assemble the desired lengths of pipe and elbows nec-
essary to reach from the burner system flue up through
the firestop. Be sure pipe and elbow connections are
fully twist-locked.
Page 16, Figure 15
3. Cut a hole in the roof using the locating hole as a center
point. (Cover any exposed open vent pipes before
cutting hole in roof). The 10
Z\x
" x 10
Z\x
" (267 x 267mm)
hole must be measured on the horizontal. Actual length
may be larger depending on the pitch of the roof. There
must be a 1" minimum clearance from the vent pipe to
combustible materials. (Insulation should be considered
a combustible material) Frame the opening as shown
on
Page 16, Figure 16.
4. Connect a section of pipe and extend up through the
hole.
