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5.
WARNING:
WARNING:
This condensing furnace is certified for installation either as
a Direct Vent (2-pipe) or Conventional (1-pipe) appliance.
Direct Vent appliances draw combustion air from the
outdoors and vent combustion products back outside.
Installation with air taken from around the furnace is often
referred to as Conventional installation - i.e. only the vent
(exhaust) pipe is provided.
8
Another important consideration when selecting one or
two pipe installation is the quality of the Indoor air which
can sometimes be contaminated with various household
chemicals . These chemicals can cause severe corrosion
in the furnace combustion system. A 2-pipe installation
has the additional advantage that it isolates the system
from the effects of negative pressure in the house.
CAUTION:
Air openings on top of the furnace and openings in closet
doors or walls must never be restricted. If the furnace is
operated without adequate air for combustion, the flame
roll-out switch will open, turning off the gas supply to the
burners.
switch must be replaced, use only the correct sized part
specified in the Replacement Parts List provided online.
Direct Vent Furnaces
Direct Vent (2-pipe) furnaces draw combustion air directly
from the outdoors and then vent the combustion products
back outside, isolating the entire system from the indoor
space. It is important to make sure that the whole system
is sealed and clearances to combustibles are maintained
regardless of the installation being in a confined or
unconfined space.
A confined space is an area with volume less than 50
cubic feet per 1,000 Btuh of the combined input rates of
all appliances drawing combustion air from that space.
Furnace closets, small equipment rooms and garages are
confined spaces. Furnaces installed in a confined space
which supply heated air to areas outside the space must
draw return air from outside the space and must have the
return air ducts tightly sealed to the furnace. Ducts must
have cross - sectional area at least as large as the free area
of their respective openings to the furnace space. Attics
or crawl spaces must connect freely with the outdoors if
they are the source of air for combustion and ventilation.
The required sizing of these openings is determined by
whether inside or outside air is used to support combustion,
the method by which the air is brought to the space, and
If a
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