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508151-01
Issue 2104
Page 32 of 72
Vent Piping Guidelines
NOTE:
Allied Air has approved the use of DuraVent
®
and
Centrotherm manufactured vent pipe and terminations as
an option to PVC. When using the PolyPro
®
by DuraVent
or InnoFlue
®
by Centrotherm venting system the vent
pipe requirements stated in the unit installation instruction
– minimum & maximum vent lengths, termination
clearances, etc. – apply and must be followed. Follow
the instructions provided with PoyPro by DuraVent and
InnoFlue by Centrotherm venting system for assembly
or if requirements are more restrictive. The PolyPro by
Duravent and InnoFlue by Centrotherm venting system
must also follow the uninsulated and unconditioned space
The A96DS2V can be installed as either a Non-Direct
Vent or a Direct Vent gas central furnace.
NOTE:
In Non-Direct Vent installations, combustion air
is taken from indoors or ventilated attic or crawlspace
and flue gases are discharged outdoors. In Direct Vent
installations, combustion air is taken from outdoors and
flue gases are discharged outdoors.
Intake and exhaust pipe sizing --
Size pipe according
to Table 18 and Table 19A through Table 19C. Count all
elbows inside and outside the home. Table 18 lists the
minimum vent pipe lengths permitted. Table 19A through
Table 19C lists the maximum pipe lengths permitted.
Ventilation Louvers
Inlet Air
(Minimum 12 in.
(305mm) above
Attic Floor)
Roof Terminated
Exhaust Pipe
Furnace
*Intake Debris
Screen
(Provided)
* See Maximum Vent Lengths table
NOTE-The inlet and outlet air openings shall each have a
free area of at least one square inch per 4,000 Btu (645mm
2
per 1.17kW) per hour of the total input rating of all equipment
in the enclosure.
Figure 21.
Equipment in Confined Space
(Inlet Air from Ventilated Attic and Outlet Air to
Outside)
Roof Terminated
Exhaust Pipe
Furnace
Ventilation
Louvers
(Crawl Space)
*Intake Debris Screen Provided
Inlet Air
Minimum
12 in. (305mm)
above Crawl
Space Floor
Coupling or
3 in. to 2 in.
Transition
(Field Provided)
* See Maximum Vent Lengths table
NOTE-The inlet and outlet air openings shall each have a
free area of at least one square inch per 4,000 Btu (645mm
2
per 1.17kW) per hour of the total input rating of all equipment
in the enclosure.
Figure 22.
Equipment in Confined Space
(Inlet Air from Ventilated Crawl Space and Outlet Air
to Outside)
AIR
INTAKE
SCREEN
(Provided)
NOTE
- Air intake screen and elbow may be rotated, so that
screen may be positioned to face forward or to either side.
Figure 23. Typical Air Intake Pipe Connections
Non−Direct Vent Applications