Combustion Air Requirements
The PERFORMANCE can use inside air if no
contaminants are present in the area of installa-
tion when venting as a Category I or Category
III appliance. If contaminants are likely to be
present in the area of installation, outside air
must be piped directly to the unit as referenced
in Section VI Venting and Combustion Air
Installation.
In order to avoid the potential of indoor
contaminates when venting as either a
Category I or Category III appliance it is
recommended to pipe uncontaminated
combustion air directly from the out-
doors to the unit as referenced in Section
VI Venting and Combustion Air
Installation.
Outside Combustion Air
Combustion air can be ducted directly from the
outside to the air inlet fitting of the PERFOR-
MANCE (Category I or Category III vent
applications) using the following materials:
-
PVC
-
Galvanized metal vent
-
Flexible metal vent
All seams and joints must be sealed with
sealant or mechanical fasteners. Do not use
tape as it is not considered a sealing material.
Air Openings
Air openings to the PERFORMANCE are
always required even if the combustion air is
obtained indoors or outdoors. These air open-
ings provide ventilation to prevent overheating
of the PERFORMANCE and its control as well
as providing combustion air.
The air openings must be sized to handle
the requirements of all appliances and air
movers (exhaust fans, etc.) contained in
the same space using the same air supply.
Methods of Accessing Combustion Air Into A
Space
Indoor Combustion Air
The methods listed in this section for
accessing Indoor
Combustion Air
assume that the infiltration rate is ade-
quate and not less than .40 ACH. For
infiltration rates less than .40 ACH, ref-
erence the NFPA 54 National Fuel Gas
Code for additional guidance.
Opening Size and Location
Openings used to connect indoor spaces shall
be sized and located in accordance with the
following see Fig. 1:
NOTICE
NOTICE
BEST PRACTICE
8
Combustion Air and Venting
Equipment Located in Confined
Spaces; All Air from inside the
building.
Fig. 1:
