International comfort products R9MSB0801716 Installation Instructions Manual page 39

INSTALLATION INSTRUCTIONS
Table 11 – Vent Termination for Direct Vent (2−pipe)
Systems
Direct Vent (2−Pipe)
Termination Kit
Termination System
2−in (51 mm) Single Penetration of
Concentric Vent Kit Wall or Roof
3−in (76 mm) Single Penetration of
Concentric Vent Kit Wall or Roof
2−in (51 mm)
2−Pipe Termination
Termination Bracket
System
Kit
3−in (76 mm) 2−Pipe Termination
Termination Bracket System
Direct Vent / 2-Pipe System
In a direct−vent (2−pipe) system, all air for combustion is taken
directly from outdoor atmosphere, and all flue products are
discharged to outdoor atmosphere. Combustion-air and vent
pipes must terminate together in the same atmospheric
pressure zone, either through the roof (preferred) or a sidewall.
See Figure 52 for references to clearances required by
National code authorities.
NOTICE
OPTIONAL CONFIGURATION FOR COMBUSTION
AIR INLET PIPE
In applications where there is a risk of excessive mois-
ture entering the combustion air inlet pipe, a moisture
trap may be added to the inlet pipe to help prevent mois-
ture from entering the furnace from the combustion air in-
let pipe. See Figure 58.
When sizing venting systems, the equivalent length of
the optional inlet pipe moisture trap must be taken into
account.
Ventilated Combustion Air Systems
In a ventilated combustion air option, the vent terminates and
discharges the flue products directly to the outdoors similar to a
direct vent system. See Figure 53 for references to clearances
required by National code authorities.
All air for combustion is piped directly to the furnace from a
space that is well ventilated with outdoor air (such as an attic or
crawl space) and the space is well isolated from the living
space or garage. Combustion air requirements for this option
are the same as the requirements for providing outside air for
combustion for a single pipe vent system. Refer to the "Air For
Combustion and Ventilation Section.
Non-Direct Vent (1-pipe) System
In a non direct-vent (1-pipe) system, all air for combustion is
taken from the area adjacent to furnace, and all flue products
440 01 6001 05
are discharged to outdoor atmosphere.
must be supplied as described in the Air For Combustion and
Ventilation Section. Do not use an abandoned chimney to
Diam. Of
supply outside air to the furnace. See Figure 53 for references
Combustion Air and
Vent Pipes to clearances required by National code authorities.
in.(mm)
A combustion air pipe to the outdoors is not required for a
1, 1−1/2, 2, or 2−1/2
single pipe vent system. A 12-in. (304 mm) long pipe with a
(25, 38, 51, 64 mm)
2−in. (50 mm Nominal Dimension− ND) tight radius 90 degree
2−1/2, 3 or 4
elbow is required to be attached to the combustion air pipe
(64, 76, 102 mm)
adapter on the furnace. (See Figure 51) This short inlet air pipe
1, 1−1/2, 2, or 2−1/2 helps to ensure stable combustion, as well as allow for sound
(25, 38, 51, 64 mm)
attenuation. To aid sound attenuation, point the inlet air pipe
away from occupants. An extra elbow and/or five feet (1.5 M) of
2−1/2, 3 or 4
pipe may be used to accomplish the sound attenuation
(64, 76, 102 mm)
function.
OPTIONAL VENTING BELOW THE FURNACE
The venting system may be positioned below the fur-
nace ONLY IF the factory accessory External Vent
Trap Kit is used. The External Vent Trap Kit is only
approved for PVC/ABS DWV venting systems.
CAREFULLY FOLLOW THE INSTRUCTIONS
PROVIDED WITH THE EXTERNAL VENT TRAP KIT
FOR LAYING OUT THE VENTING SYSTEM AND
THE DRAIN SYSTEM. The instructions included with
this furnace DO NOT APPLY to vent systems that are
located below the furnace.
CARBON MONOXIDE POISONING HAZARD
Failure to follow the instructions outlined in Locating the
Vent Termination for each appliance being placed into
operation could result in carbon monoxide poisoning or
death.
The instructions included with this furnace DO NOT AP-
PLY to vent systems that are located below the furnace.
CAREFULLY
PROVIDED WITH THE EXTERNAL VENT TRAP KIT
FOR LAYING OUT THE VENTING SYSTEM AND THE
DRAIN SYSTEM when all or part of the venting system
is placed below the furnace.
Proper configuration of the venting and drain system is
critical when placing all or part of the venting system be-
low the level of the furnace. VENT GASSES COULD BE
RELEASED FROM THE DRAINAGE SYSTEM, if the in-
structions provided with the External Vent Trap Kit are
not followed.
Specifications subject to change without notice.
Gas Furnace: R9MSB
NOTICE
WARNING
!
FOLLOW THE
Air for combustion
INSTRUCTIONS
39