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18-CE18D1-1B-EN
Furnace Combustion Air Exhaust Options
Important:
All plugs must be in place for sealed combustion.
Note:
Default is left side for electric and natural gas connections.
Default for the combustion air inlet and exhaust is top of the
furnace.
Important:
If the locations are changed from the defaults, the
default holes not being used must be plugged.
Note:
If the electrical and natural gas connections are moved to the
right side, remove the plugs and move them to the left side.
The grommets will move from the left side to the right side.
Note:
The grommets are different for the natural gas and condensate
connections.
The following sections give instructions for the
different furnace orientations and the options for
venting the inlet and exhaust combustion air.
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po
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an
ntt:: When looking at the different orientations,
the direction of the combustion air exhaust
in the illustration’s description is after the
furnace has been rotated, if needed.
Table 5. Combustion Air Venting Options
Refer to the illustrations below to find the approved venting options for upflow and horizontal left furnace models.
Important:
The combustion air exhaust must be vented to the outdoors.
Note:
The combustion air inlet does not have to be on the same side as the combustion air exhaust.
Note:
Right side combustion air entry is allowed in upflow applications.
Upflow Orientation or Installation
Combustion air exhaust vented out top.
Combustion air exhaust vented through left side.
Horizontal Left Orientation or Installation
Combustion air exhaust vented out top.
Combustion air exhaust vented through left side.