AHRI (-)98VA060M317USA, Installation Instructions Manual

Page: 33 / 108

33
Ve
ntin
g
DIRECT-VENT (2-PIPE)
INSTALLATIONS
The field-supplied vent system used for direct-vent instal-
lations uses 2 pipes; one inlet pipe for supplying the com-
bustion air to the furnace, and an exhaust (or flue) pipe for
transferring the flue products to the outside. The flue pipe
is elevated at least 12 inches above the air intake pipe for
all vertical installations to prevent flue gas recirculation
during operation.
The furnace combustion air inlet must be located a mini-
mum of 3 feet from the vent of any other gas or fuel-burn-
ing appliance or clothes dryer to prevent recirculation of
the flue gases into the furnace combustion air inlet. The
only exception to this requirement is the case of multivent-
ing two or more furnaces, which is covered in the section
on multiventing of these instructions.
Direct-Vent systems must be installed so that the vent and
combustion air intake pipes terminate in the same atmos-
pheric pressure zone.
DIRECT VENT
GENERAL VENTING REqUIREMENTS AND
GUIDELINES
!
WARNING
ALL FURNACE INSTALLATIONS MUST COMPLy
WITH THE NATIONAL FUEL GAS CODE OR, IN
CANADA, CSA B149.1; NATURAL GAS AND
PROPANE INSTALLATION CODE AND LOCAL
CODES TO PROVIDE ADEqUATE COMBUSTION
AND VENTILATION AIR FOR THE FURNACE. FAIL-
URE TO DO SO CAN RESULT IN ExPLOSION, FIRE,
PROPERTy DAMAGE, CARBON MONOxIDE POI-
SONING, PERSONAL INJURy OR DEATH.
!
WARNING
READ AND FOLLOW THE GENERAL VENTING RE-
QUIREMENTS AND GUIDELINES OF THIS MANUAL
FOR ADDITIONAL VENTING REqUIREMENTS PER-
TAINING TO ALL FURNACE INSTALLATIONS (IN-
CLUDING DIRECT AND NON-DIRECT VENTING).
FAILURE TO FOLLOW ALL INSTRUCTIONS IN THIS
MANUAL CAN RESULT IN EqUIPMENT FAILURE,
EqUIPMENT DAMAGE, PROPERTy DAMAGE, PER-
SONAL INJURy OR DEATH.
OPTION 1: STANDARD VERTICAL DIRECT-VENT TERMINATION
Figure 16 below shows a standard vertical termination for direct venting installations. Maintain the dimensions specified in
this drawing for vertical venting of direct-vent furnace installations. Specific details of the roof penetration can be found in
Figure 17 .
ST-A1194-18
FIG J
SEE FIGURE 21 FOR
MORE INFORMATION
12” VERTICAL SEPARATION
BETWEEN COMBUSTION AIR
INTAKE AND VENT.
NOTE: IF 3
(
Ø VENTING IS
USED, BOTH PIPES (INTAKE
AND EXHAUST) MUST BE
REDUCED TO 2
(
Ø BEFORE
PENETRATING THE ROOF.
FIGURE 16
DIRECT VENT FURNACE PENETRATIONS
ROOF INTAkE/VENT