11
for combustion and ventilation. (See Figures 7
and 8.)
Outdoor Air Through Horizontal Openings or Ducts
If combustion air is taken from outdoors through
horizontal ducts, the openings must each have
free area of at least one square inch per 2000
Btuh of total appliance input. Ducts must have
cross-sectional area at least as large as the free
area of their respective openings to the furnace
space. (See Figure 9.)
CAUTION:
Do not supply combustion air from an
attic space that is equipped with power
ventilation or any other device that may
produce a negative pressure.
VENTING REQUIREMENTS
This section specifi es installation requirements
for vent and “2-pipe” combustion air piping. For
“one pipe” installations, install vent piping per
this section and provide air for combustion and
ventilation per the previous section. The capacity
**NOTES
1.
Subtract 2.5 ft. for each additional 2”
long
radius elbow, 5 ft. for each additional 2”
short
radius elbow, 3.5’
for each additional 3”
long
radius elbow, and 7’ for each additional 3”
short
radius elbow.
2.
Two 45 degree elbows are equivalent to one 90 degree elbow.
3.
Do not include termination elbows in calculation of vent length
4.
This table is applicable for elevations from sea level to 2000 ft. For higher elevations decrease vent pipe
lengths by 8% per 1000 ft. of altitude.
5.
Only the above pipe materials are approved for use with these condensing furnaces.
Table 3. Vent Table
table provided in this section applies to the total
of vent and combustion air piping for either type
of installation.
These condensing furnaces are classifi ed as
“Category IV” appliances, which require special
venting materials and installation procedures.
Category IV appliances operate with posi-
tive vent pressure and therefore require vent
systems which are thoroughly sealed. They
also produce combustion condensate, which is
slightly acidic and can cause severe corrosion
of ordinary venting materials. Furnace operation
can be adversely affected by restrictive vent
and combustion air piping. Therefore, vent and
combustion air piping lengths must conform
completely to the requirements of Table 3.
The furnace must be vented to the outdoors.
It must not be vented in common with any
other appliance, even if that appliance is of the
condensing type. Common venting can result
in severe corrosion of other appliances or their
venting and can allow combustion gases to
escape through such appliances or vents. Do
not vent the furnace to a fi replace chimney or
building chase.
APPLICATION
SINGLE PIPE LENGTH (ft.)
with 1 long radius elbow**
DIRECT VENT, DUAL PIPE LENGTH (ft.)
with 1 long radius elbow on each pipe**
PVC,CPVC or ABS
SCH. 40 Pipe Size
Outlet
Outlet
Inlet/Outlet
Inlet/Outlet
Inlet/Outlet
2”
3”
2”
2”
3”
2”
3”
3”
Models *TE 060
65
200
30
30
40
40
110
110
Models *TE 080
45
200
30
30
40
40
110
110
Models *TE 100
40
200
25
25
40
40
110
110
Models *TE 120
40
200
20
20
40
40
110
110
