27
26
NOTES:
(1)
If an offset is necessary in the attic to avoid
obstructions, it is important to support the vent pipe
every 3 feet (914 mm), to avoid excessive stress
on the elbows, and possible separation. Wall straps
are available for this purpose (see Figure 32).
(2)
When ever possible, use 45
°
degree elbows instead
of 90
°
degree elbows. The 45
°
degree elbow offers
less restriction to the flow of flue gases and intake
air.
(3)
For multi story installations; a ceiling firestop is
required at the second floor, and any subsequent
floors (see Figure 33). The opening should be
framed to 10” (254 mm) x 10” (254 mm) inside
dimensions, in the same manner as shown in Figure
23.
(4)
Any occupied areas above the first floor,
including closets and storage spaces,
which the vertical vent passes through,
must be enclosed. The enclosure may be
framed and sheet-rocked with standard
building materials. However consult
the appliance manufactures installation
instructions for the minimum allowable
clearance between the outside of the vent
pipe, and the combustible surfaces of
the enclosure. Do not fill any required air
spaces with insulation.
Figure 32: Use of Wall Straps.
Figure 33: Multi-Story Vent Pipe Installation.
Initial Installation
QUALIFIED INSTALLERS ONLY
