Locating & Cutting Roof Openings - Nordyne M1MB 056 Installation Instructions Manual

Figure 18. Example of 2½ / 12 Slant Jack
with Flashing
ROOF JACK IF ROOF
SERIES PITCH IS:
2" in 12"
2-1/2" in 12"
3" in 12"
"F Series
3-1/2" in 12"
4" in 12"
4-1/2" in 12"
5" in 12"
"S" Series
5-1/2" in 12"
(2.5 / 12 Pitch only)
6" in 12"
6-1/2" in 12"
Optional deck fl ashings for fl at and 2.5/12 pitch roof jacks.
4/12 pitch roof jacks not applicable.
Table 5. Slant Deck Flashings
Locating & Cutting Roof/Ceiling Openings
IMPORTANT:
Do not allow debris to fall into the furnace.
This could cause unsafe operation and void
the furnace warranty. Use the top cap that
comes with the furnace packaging (or alternate
protector) to prevent debris from falling into the
furnace before the fi nal roof jack connection
is made
NOTE: Refer to the installation instructions provided
with optional air conditioning packages when installing
furnaces with optional cooling coil cabinet or with optional
C* series indoor coils.
1. Locate center of Roof Jack opening, measure 13 1/2"
from the rear wall of closet or alcove along the center
line of furnace and fl oor opening. See Figure 19.
2. Cut ceiling and roof holes:
• Ceiling = 8 3/4" (222 mm) diameter
• Roof = 9 3/8" (238 mm) diameter
12
SLANT DECK "X"
FLASHING FACTOR
NUMBER IS:
903893 (2.5/12) 2-1/8"
903893 (2.5/12) 2-1/2"
903894 (3/12) 2-7/8"
903894 (3/12) 3-1/4"
903895 (4/12) 3-5/8"
903895 (2.5/12) 2-1/8"
903895 (2.5/12) 2-1/2"
903894 (3/12) 2-7/8"
903894 (3/12) 3-1/4"
903895 (4/12) 3-5/8"
REAR WALL OF CLOSET OR ALCOVE
24"
Figure 19. Cut-Out Dimensions for
Flue & Roof Jack
Installing The Roof Jack
1. Apply caulking compound on underside of roof fl ashing
to form a continuous strip at least 3/8" wide around the
underside of the perimeter of the fl ashing. See Figures
20 or 21 (page13).
2. Connect Roof Jack Assembly to the furnace. Insert
telescoping Roof Jack Assembly through the opening
cut on the roof.
3. Connect fl ue pipe to fl ue collar of furnace. See Figure
22 (page 13).
4. Connect combustion air pipe to furnace collar with
sheet metal screw (See Figure 22).
NOTES:
• It is recommended that the connection of the combustion
air pipe to the furnace be made before the fl ashing is
secured to the roof to maintain alignment of roof jack
and furnace connections.
• For replacement furnaces, be sure the inner fl ue pipe
connects over the furnace vent collar. DO NOT use a
smaller diameter inner fl ue pipe which could slide
inside the furnace vent collar and restrict the fl ow
of furnace fl ue products.
5. Attach Roof Flashing. If necessary, shift roof fl ashing
slightly in the roof opening so that assembly is in
alignment with furnace.
NOTE: If fl ashing is mounted on 12 degree angle, it
may be necessary to adjust the angle to match the roof
pitch; (1/12 - 4/12 maximum).
6. Press down fi rmly on roof fl ashing (over caulking) to
make the seal with roof water tight.
7. Secure fl ashing with appropriate fasteners. NOTE: For
added protection against leaks, coat the fl ashing plate
and fasteners with approved roofi ng compound.
20"
C L
10"
C L
FURNACE
OUTER
DOOR