Ruud 801P SERIES, Installation Instructions Manual

Page: 19 / 52

19
COMBUSTION AND VENTILATION AIR (cont.)
GENERAL INFORMATION
The furnace must be vented in accordance with these instructions,
National Fuel Gas Code, ANSI Z223.1 and/or the Natural Gas In-
stallation Code, CSA-B149.1 & .2 and requirements or codes of
the local utility or other authority having jurisdiction.
DRAFT INDUCER
FURNACE CATEGORY INFORMATION
This furnace is shipped as a Category I type induced draft fur-
nace. A Category I furnace operates with a nonpositive vent pres-
sure and has a vent gas temperature at least 140°F above the
dew point of the vent gases. A Category
I type may be a draft
hood equipped furnace or have a fan assisted combustion sys-
tem (induced draft). The inducer is used to pull flue products
through the combustion chamber and as they leave the furnace,
most of the energy has been dissipated. The buoyant effect of the
flue gases provides venting to the outdoors.
During the off cycle, the inducer is off and there is very little flow
through the vent, cooling the vent. During the on cycle there is no
dilution airflow, as with a draft hood type furnace. Although the
vent heats up rapidly without dilution air, the flue products contain
more water vapor, which results in a higher dew point tempera-
ture. It is most
important that you follow the guidelines in these
instructions to prevent the possible formation of condensation in
the venting system.
As a Category I furnace it may be vented vertically with type B-1
vent pipe and also may be common vented, as described in
these instructions.
IMPORTANT APPLICATION NOTES
When the furnace is used as a replacement, the existing vent
system should be inspected to assure that there are no obstruc-
tions, blockage, or any signs of corrosion and is properly sized for
use with this furnace.
NOTE: When the vent table permits more than one diameter of
pipe for a connector or vent, the smallest permitted diameter
must be used.
Vent pipe may be type “B-1,” either rigid or suitable flexible con-
struction that carries a U.L. listing.
Common venting is allowed with vertical B-1 vent systems, and
lined masonry chimneys. Follow the National Fuel Gas Code,
ANSI Z223.1 and/or the Natural Gas Installation Code, CSA-
B149.1 & .2 for proper installation practices.
NOTE: Follow combustion air instructions as outlined in this man-
ual.
Single wall vent connectors to “B-1 vent or masonry chimneys”
may be used under the guidelines of the National Fuel Gas Code,
ANSI Z223.1 and/or the Natural Gas Installation Code, CSA-
B149.1 & .2.
The entire length of the vent connector shall be readily ac-
cessible for inspection, cleaning and replacement.
“B-1” VERTICAL VENTING
NOTE: Refer to the National Fuel Gas Code, ANSI Z223.1 and/or
the Natural Gas Installation Code,
CSA-B149.1 & .2.
Type “B-1” vents must be installed in accordance with the terms
of their listings and the vent manufacturer’s instructions.
“B-1” vents must be supported and spaced in accordance with
their listings and the manufacturer’s instructions. All vents must
be supported to maintain their minimum clearances from com-
bustible material.
*NOTE: All furnaces have a 3” vent connection as shipped from the fac-
tory. (-)801P models are also equipped with a 4” adapter. A 3” to 4”, 3” to
5”, or 4” to 5” vent transition may be required when vertically vented or
common vented with metal vent pipes.
THE VENT TRANSITION CON-
NECTION MUST BE MADE AT THE FURNACE VENT EXIT. It must origi-
nate with an adapter if required, at the furnace flue collar and terminate
either in a listed cap or roof assembly. When common venting, the vent
connector size may differ from the above diameters depending on appli-
cation. See National Fuel Gas Code ANSI Z223.1 or latest edition tables.
!
WARNING
DEVICES ATTACHED TO THE FLUE OR VENT FOR THE
PURPOSE OF REDUCING HEAT LOSS UP THE CHIMNEY
HAVE NOT BEEN TESTED AND HAVE NOT BEEN IN-
CLUDED IN THE DESIGN CERTIFICATION OF THIS FUR-
NACE. WE, THE MANUFACTURER, CANNOT AND WILL
NOT BE RESPONSIBLE FOR INJURY OR DAMAGE
CAUSED BY THE USE OF SUCH UNTESTED AND/OR UN-
CERTIFIED DEVICES, ACCESSORIES OR COMPONENTS.
!
WARNING
VENT PIPE ATTACHING HOLES MUST BE PREDRILLED
IN THE DRAFT INDUCER COLLAR TO PREVENT DAMAG-
ING THE INDUCER. DRILL 1/8
” DIAMETER HOLES
THROUGH THE VENT PIPE AND COLLAR AND USE #8
SCREWS TO ATTACH. SEE FIGURE 16. FAILURE TO FOL-
LOW THIS WARNING CAN CAUSE RECIRCULATION OF
FLUE PRODUCTS CAUSING CARBON MONOXIDE POI-
SONING RESULTING IN PERSONAL INJURY OR DEATH.
VENTING
VERTICAL VENTING
Categorized
Furnace Vent
Input Size Recommended
(See NFGC)
50K 3
”
75K *4
”
100K *4
”
125K *5
”
150K *5
”
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