17
75D2523
MDV Series Direct Vent Gas Fireplace
rear wall Vent InstallatIon
(5"
x
8" VentIng only)
When installed as a rear vent unit this appliance may be
vented directly to a termination located on the rear wall
behind the appliance. Only an MHSC brand termination
is allowed for this application.
•
The maximum horizontal distance between the rear
of the appliance and the termination is 20" (508 m).
Figure 14.
•
Only one 45° elbow is allowed in these installations.
VentIng InstallatIon
1. Rigid vent pipes and fittings have special twist-lock
connections. Assemble the desired combination of pipe
and elbows to the appliance adapter.
twist-lock procedure:
The female ends of the pipes
and fittings have three locking lugs (indentations).
These lugs will slide straight into matching slots on
the male end of adjacent pipes and fittings. Push the
pipe sections together and twist one section clockwise
approximately one-quarter turn until the sections are
fully locked.
Figure 15
note: sealant is not required to assemble fireplace
venting. do not use silicone sealant at the inner flue
exhaust connections.
Figure 15 -
Rigid Vent Pipe
Connections
note: horizontal runs of
vent must be supported
every 3' (914 mm). use wall
straps for this purpose.
FP1953
rigid pipe
Female
Locking Lugs
Male Slots
FP1953
2. Refer to the venting and termination instructions for
further instructions.
3. Locate and cut the vent opening in the wall. For com-
bustible walls first frame in opening.
combustible Interior walls:
Cut a 12
Z\x
"H x 10
Z\x
" W
(318 x 267 mm) hole through the interior wall.
combustible exterior walls:
Cut a 10
Z\x
"H x 10
Z\x
"W
(267 x 267 mm) square hole through the exterior
wall frame.
Figure 16
noncombustible walls:
Hole opening should be 8
Z\x
"
(216 mm) in diameter.
4. The center of the hole should align with the center line
of the horizontal rigid vent pipe end. Allow 1/4" minimum
rise per foot.
Figure 16
5. Apply a bead of non-hardening mastic around the
outside edge of vent cap. Position the vent cap in the
center of hole on the exterior wall with the word “UP”
on the vent cap facing up. Insure proper clearance of
1" to combustibles is maintained. Attach the vent cap
with four wood screws supplied.
Figure 17
note:
Replace the wood screws with appropriate fasteners
for stucco, brick, concrete, or other types of siding.
For vinyl siding, stucco, or wood exterior use vinyl siding
standoffs between vent cap and exterior wall for Simpson
or Selkirk Terminations only. The vinyl siding standoff pre-
vents excessive heat from melting the vinyl siding material.
note:
MHSC Termination does not require standoff. Bolt
the vent cap to the standoff or wall. Apply non-hardening
mastic around outside edge of the standoff instead of the
vent cap assembly. Use wood screws provided to attach
the standoff.
Figure 18
Figure 16 -
Exterior Wall Framing Dimensions
VO584-100
Vent Opening
2/99 djt
10
Z\x
"
(267 mm)
10
Z\x
"
(267 mm)
combustible wall
framing
VO584-100
8
Z\x
"
(216 mm)
FP1188
rear wall install
20”
(508 mm)
Max.
20”
(508 mm)
Max.
Figure 14 -
Rear Vent Application,
Maximum Horizontal Distance
rear Vent top View
FP1188
