Monessen Hearth SS38 - Manual (Page 17)

17 46D0232
SS38 Direct Vent Gas Stove VENTING INSTALLATION
FLAT CEILING INSTALLATION
1. Cut a 9Z\x" (241 mm) square hole in the ceiling using the
locating hole as a center point The opening should be
framed to 9Z\x" x 9Z\x" (241 x 241 mm) inside dimensions
as shown in Figure 20 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 19. Otherwise, install
firestop below the framed hole. The firestop should be
installed with no less than three nails per side. Figure
20.
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 13, Figure 10
3. Cut a hole in the roof using the locating hole as a center
point. (Cover any exposed open vent pipes before cut-
ting hole in roof). The 9Z\x" x 9Z\x" (241 x 241 mm) 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 com-
bustible materials. (Insulation should be considered a
combustible material) Frame the opening as shown in
Figure 11 on Page 14.
FP1969
firestop w room above
Figure 19 -
If area above is a room, install firestop above framed
hole as shown
Firestop
Nails
FP1969
9
1 /
2 "
9
1
/
2
"
FP1970
firestop no room
Figure 20 - If area above is not a room, install
firestop below framed hole as shown
Nails
Firestop
FP1970
4. Connect a section of pipe and extend up through the
hole.
NOTE: If an offset is needed to avoid obstructions, you
must support the vent pipe every three (3) feet. Use wall
straps for this purpose. See Figure 18, page 17. Whenever
possible, use 45° elbows instead of 90° elbows. The 45°
elbow offers less restriction to the flow of the flue gases
and intake air.
5. Place the flashing over the pipe section(s) extending
through the roof. Secure the base of the flashing to
the roof and framing with roofing nails. Be sure roofing
material overlaps the top edge of the flashing as shown
in Figure 18, page 17. There must be a 1" clearance
from the vent pipe to combustible materials.
6. Continue to add pipe sections until the height of the vent
cap meets the minimum building code requirements.
NOTE: You must increase vent height for steep roof
pitches. Nearby trees, adjoining roof lines, steep pitched
roofs, and other similar factors may cause poor draft or
down-drafting in high winds. Increasing the vent height
may solve this problem.
NOTE: If the vent pipe passes through any occupied areas
above the first floor, including storage spaces and closets,
you must enclose pipe. You may frame and sheetrock the
enclosure with standard construction material. Make sure
to meet the minimum allowable clearances to combustibles.
Do not fill any of the required air spaces with insulation.
CATHEDRAL CEILING INSTALLATION
IMPORTANT: Review all information on previous page
before planning this installation. Cathedral ceiling
installations can be very tricky.
1. Remove shingles or other roof covering as necessary
to cut the rectangular hole for the support box. Mark the
outline of the cathedral ceiling support box on the roof
sheathing using the locating hole as a center point.
2. Cut the hole 1/8" larger than the support box outline.
Figure 21
3. Lower the support box through the hole in the roof until
the bottom of the box extends at least 2" ( mm) below
the ceiling. Figure 21. Align the support box vertically
and horizontally using a level. Temporarily tack the sup-
port box in place through the inside walls and into the
roof sheeting.
4. Using tin snips, cut the support box from the top corners
down to the roofline and fold the resulting flaps over the
roof sheeting. Figure 22. Apply a bead of non-hardening
mastic around the top edges of the support box to make
a seal between the box and the roof. Nail in place with
roofing nails. Remove any combustible material that
might be inside the support box.
5. Complete the cathedral ceiling installation by following
the same procedures outlines in Steps 2 through 6 for
Flat Ceiling Installation, Page 17 and above.