Nordyne Downflow Direct Vent Forced Air Gas Oil Furnaces SERIES M1B - Manual (Page 13)

13
Secure roof jack with
appropriate fasteners
after connecting to
furnace
Caulk under roof
flashing to prevent
water leakage
Roof
Ceiling
Optional 2-piece ceiling
ring #902521
Figure 20. Flat Roof
Upper Roof Jack Section
Secure lower roof
jack section with
no. 10 S.M. screws
Caulk under roof
flashing to prevent
water leakage
Optional Slant
Deck Flashing
Secure flashing
with appropriate
fasteners
Ceiling
Figure 21. Pitched Roof
Figure 22. Combustion Air Pipe Connection
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.
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.
4. Connect combustion air pipe to furnace collar
with sheet metal screw (See Figure 22).
NOTE: 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.
NOTE: 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.
Installation of Transit-Mode Venting System
Manufactured Home Factory
1. Furnace must be installed in accordance to
furnace installation manual.
2. Select appropriate Roof Jack from Table 4
(page 11).
3. Roof Jack (less upper Roof Jack crown), with
weather cap to be installed as described under
Install Roof Jack.
NOTE: Upper Roof Jack crown to be stored in
a prominent location inside manufactured home
until on-site installation.