Monessen Hearth KHLDV400 - Manual (Page 20)

20 73D0024
KHLDV Series Gas Fireplace VentnG InStaLLatIOn
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 1 /
2
"x10 1/2 " (241mm x 241mm) 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).
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 19. 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. 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 require-
ments.
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
clearance spaces with insulation.
terMInatIOn HeIGHtS FOr VentS aBOVe FLat Or SLOpeD rOOFS
2 ft.
Min.
2 ft. Min.
X
12
H*
FP1971
Min chimney clearance
Horizontal Overhang
Termination Vent
Lowest
Discharge
Opening
Storm Collar
Flashing
Concentric
Vent Pipe
1" Minimum
Clearances to
Combustibles
Vertical Wall
FP1971
Figure 23 -
Minimum Chimney Clearance
roof pitch H (feet)
Flat to 6/12 1.0
Over 6/12 to 7/12 1.25
Over 7/12 to 8/12 1.5
Over 8/12 to 9/12 2.0
Over 9/12 to 10/12 2.5
Over 10/12 to 11/12 3.25
Over 11/12 to 12/12 4.0
*H - Minimum height from roof to
lowest discharge opening of vent