5894307-UIM-B-0920
20
Johnson Controls Ducted Systems
DOWNWARD VENTING
In some applications, it may be necessary to run the vent pipe and air
intake downwards. If this is to be done, adhere to the following rules:
• A condensate trap hose must be connected to both the air intake
pipe and the vent pipe at the lowest part of the horizontal run.
• The condensate drain trap must have a trap of a minimum of 6 in.
• The total vertical downward distance must not exceed 16 ft.
• The condensate drain hose must be connected to a condensate
drain pump, to an open or vented drain, or into the condensate
drain line from the furnace.
• The condensate drain lines must not pass through unconditioned
spaces where the temperature may fall below freezing.
• The condensate drain lines must be primed at the initial start-up
before the start of heating season.
COMBUSTION AIR SUPPLY
All installations must comply with Section 5.3, Air for Combustion and
Ventilation of the National Fuel Gas Code, ANSI Z223.1 or Sections
7.2, 7.3, or 7.4 of CAN/CGA B149.1 or B149.2 Installation Code - latest
editions.
Install this furnace using one of the following combustion air intake con-
figurations.
•
OUTDOOR COMBUSTION AIR:
This is a direct vent configura-
tion where the combustion air is supplied through a PVC or ABS
pipe that is connected to the PVC coupling attached to the fur-
nace and is terminated in the same atmospheric zone as the
vent. This type of installation is approved on all models. See Fig-
ures 21 and 22.
•
AMBIENT COMBUSTION AIR:
Combustion air is supplied from
the area surrounding the furnace through openings in the furnace
casing. The combustion air and the vent pipes are not terminated
in the same atmospheric zone. See Figure 20 for vent termina-
tions. See the Ambient Combustion Air Supply section for proper
installation. See Figure 28.
•
VENTILATED COMBUSTION AIR:
Combustion air is supplied
through a PVC or ABS pipe that is connected to the PVC coupling
attached to the burner box and is terminated in a ventilated attic
or crawl space. The combustion air and the vent pipes are not ter-
minated in the same atmospheric zone. See Figure 29 for attic
and crawl space termination. Only the combustion air intake can
terminate in the attic. The vent must terminate outside.
Outdoor Combustion Air
Combustion Air Intake/Vent Connections
This installation requires combustion air to be brought in from outdoors.
This requires a correctly sized pipe (shown in Figure 25) that brings air
in from the outdoors to the furnace combustion air intake collar on the
burner box. The second pipe (shown in Figure 25) is the furnace vent
pipe.
The combustion air intake pipe must be located either through the wall
(horizontal or side vent) or through the roof (vertical vent). Care must be
taken to locate side vented systems where trees or shrubs do not block
or restrict supply air from entering the terminal.
The terminal assembly must be located as far as possible from a swim-
ming pool or a location where swimming pool chemicals might be
stored. Make sure the terminal assembly follows the outdoor clear-
ances listed in the VENT APPLICATIONS AND TERMINATION section.
Figure 23:
Double Horizontal Combustion Air Intake and Vent
Termination
Figure 24:
Double Vertical Combustion Air Intake and Vent
Termination
Figure 25:
Downward Venting
VENT
2”
MIN.
COMBUSTION AIR
MIN.
6”
16’ MAX
6” MIN.
6” MIN.
NOTICE
An optional plastic birdscreen is shipped in the loose parts bag with
every furnace. This can be installed in the intake collar to prevent any
small objects from entering the furnace. The birdscreen cannot be
used if the intake drain is installed.
Figure 26:
Direct Vent Air Intake Connection and Vent Connection
AIR INTAKE PIPE
CONNECTS TO COLLAR
ON CASING TOP
INTAKE DRAIN
VENT PIPE
CLAMPS INTO
OUTLET OF
VENT COUPLING
RAIN GUTTER
A1130-001
