Filter
Top Products
9
Category IV Venting
A CATEGORY IV POSITIVE
PRESSURE VENTING SYSTEM
FIG. 10 Basic Category IV Venting - Vertical
FIG. 11 Basic Category IV Venting - Horizontal
A Category IV venting system for the flue products is required on
all models of this appliance. A Category IV vent ing system
operates with a positive pressure in the vent. This positive pressure
is generated by the internal combustion air blower which operates
the combustion process and also ex hausts the flue products from
the build ing. The Category IV flue from this appliance can NOT
be combined with the vent from any other appliance. The Category
IV flues from multiple ap pli anc es can NOT be combined into a
common vent. The Category IV flue from this appliance must be
a dedicated stack. The flue from this Category IV ap pli ance must
have all vent joints and seams sealed gas-tight. A Category IV
vent system has specific vent material and installation requirements.
The flue products in the vent system may be cooled below their
dew point and form condensate in the flue. The
ma te ri als used for a Category IV vent must be resistant to any
corrosive damage from flue gas condensate. The flue from a
Category IV vent system must have a condensate drain with
provisions to properly collect and dispose of any condensate that
may occur in the vent ing system.
Category IV Flue Pipe Materials
Select venting material from the fol low ing specified vent
distributors:
Heat-Fab Inc. Saf-T CI Vent with AL29-4C stainless steel
(Call 1-800-772-0739 for nearest distributor)
Protech Systems Inc. Fas N Seal Vent with AL29-4C stainless
steel (Call 1-800-766-3473 for nearest distributor)
Z-Flex Z-Vent with AL29-4C stainless steel
(Call 1-800-654-5600 for nearest distributor)
Or other listed Category IV vent sys tems suitable for a condensing,
pos i tive pressure gas fired appliance.
Venting Guidelines for a Category IV Vent
The connection from the appliance vent to the stack or vent
termination out side the building MUST be made with listed
Category IV vent system and must be direct as possible with no
reduction in diameter. The Category IV vent and accessories, such
as firestop spacers, thimbles, caps, etc., MUST be installed in
accordance with the vent manufacturers instructions. The vent
connector and firestop must provide correct spacing to combustible
surfaces and seal to the vent connector on the upper and lower sides
of each floor or ceiling through which the vent connector passes.
In a typical installation, each appliance must have a dedicated
Category IV flue with no other appliance interconnected to any
part of the dedicated flue. Each appliance MUST connect to the
dedicated flue stack using a properly sealed vent adapter provided
by the vent manufacturer. The flues from multiple Intelli-Fin
appliances may only be combined when using an engineered vent
system incorporating an induced draft fan to ensure that flue
products will be properly exhausted from the building at all times.
Failure to use a properly sized induced draft fan on a combined vent
installation may result in a hazardous condition where flue gases
spill into an occupied living space. Consult the induced draft fan
manufacturer to size the induced draft fan and to determine the
diameter of the common vent pipe required for a combined vent
installation.