31
Venting and Combustion Air Installation
Multiple Vent Terminations
For multiple unit installation venting horizon-
tally, it is recommended to vent as direct vent
using the Horizontal Wall Thimble Kit or
Horizontal Concentric Kit. The terminations
on these installations must maintain the same
horizontal centerline and be spaced a minimum
18 inches from center to center.
For multiple unit installation venting vertically,
it is recommended to vent as direct vent using
Triangle Tube Vertical Concentric Vent Kit.
The concentric vent / combustion air termina-
tions must maintain a minimum 18 inch spac-
ing from vent centerline to vent centerline.
Locating the Combustion Air Inlet
When ducting outside combustion air directly
to the unit when venting as a Category I or
Category III appliance the installer must use
the following guidelines:
1. The total equivalent length of the air inlet
duct should not exceed 100 feet as given in
Table 2, page 35.
2. The installer must consider the following
when determining the location of the com-
bustion air inlet:
-
The air inlet must terminate at least 12
inches above grade or projected snow
line.
-
The combustion air inlet must be located
a minimum 12 inches from the vent ter-
mination when installing separate air
and vent pipes through a side wall. This
does not apply to horizontal concentric-
direct venting applications using the
Horizontal Wall Thimble kit. See Fig.
23, page 37.
-
The combustion air inlet should not be
located above the vent termination.
-
The combustion air inlet must be locat-
ed in the same pressure zone as the vent
termination. This does not apply when
venting the appliance as Category I.
Venting Option - Non Direct Vent / Vertical
In this vent application the PERFORMANCE
is vented vertically through the roof or an
unused chimney using only approved 3 inch
stainless steel vent material and using room air
for combustion.
The installer should consider the following
when choosing this vent option:
a. The vent system must contain a con-
densate trap located no higher than 2
feet above the unit. As shown in Fig. 19
page 35.
b. The vent system must pitch back to the
unit 1/4 inch per foot or as specified by
the vent manufacturer.
c. Clearance to combustibles must be
maintained per the vent manufacturer’s
requirements. Refer to the vent manu-
facturer’s installation instructions for
additional details.
d. At a minimum, a 3-inch elbow with
screen should be placed on the combus-
tion air inlet of the unit. This will pre-
vent an accidental blockage should
anything be placed on top of the unit.
When using an unused chimney as a
means of a raceway for the 3 inch vent,
the surrounding space cannot be used to
draw combustion air.
Venting Option - Direct Vent / Vertical
In this vent application the PERFORMANCE
is vented vertically through the roof or an
unused chimney using the Triangle Tube con-
centric Vertical Vent Kit.
NOTICE
