13
T
ERMINATION
L
OCATIONS
NOTES:
Refer to
Section IV, Location Requirements and
Considerations
for combustion air contaminant restrictions.
The following bullets and diagram describe the restrictions concern-
ing the appropriate location of vent/flue pipe and combustion air
intake pipe (when applicable) terminations. Refer to
Non-Direct
Vent (Single Pipe) Piping
and
Direct Vent (Dual Pipe) Piping
lo-
cated in this section for specific details on termination construction.
•
All terminations (flue and/or intake) must be located at
least 12 inches above ground level or the anticipated snow
level.
•
Vent terminations (non-direct and direct vent) must
terminate at least 3 feet above any forced air inlet located
within 10 feet.
NOTE:
This provision does not apply to the combustion
air intake termination of a direct vent application.
•
The vent termination of a
non-direct
vent
application must
terminate at least 4 feet below, 4 feet horizontally from, or
1 foot above any door, window, or gravity air inlet into any
building.
•
The vent termination of a
direct vent
application must
terminate at least 12 inches from any opening through
which flue gases may enter a building (door, window, or
gravity air inlet).
•
The vent termination of vent pipe run vertically through a
roof must terminate at least 12 inches above the roof line
(or the anticipated snow level) and be at least 12 inches
from any vertical wall (including any anticipated snow build
up).
•
A vent termination shall not terminate over public walkways
or over an area where condensate or vapor could create
a nuisance or hazard or could be detrimental to the
operation of regulators, relief valves, or other equipment.
•
The combustion air intake termination of a direct vent
application should not terminate in an area which is
frequently dusty or dirty.
12"
Non-Direct Vent
Vent/Flue Termination
No Terminations
Above Walkway
12"
min.
4'
min.
Non-Direct Vent
Vent/Flue Termination
Direct Vent
Vent/Flue Termination
<10'
Forced Air
Inlet
Non-Direct Vent
&
Direct Vent
Vent/Flue Terminations
Grade or Highest
Anticipated
Snow Level
3' min.
12" min.
4' min.
12" min.
Vent Termination Clearances
NOTE:
In Canada, the Canadian Fuel Gas Code takes precedence
over the preceding termination restrictions.
vent
installation requires only a vent/flue pipe, while a
direct vent
installation requires both a vent/flue pipe and a combustion air in-
take pipe. Refer to the appropriate section for details concerning
piping size, length, number of elbows, furnace connections, and
terminations.
M
ATERIALS
AND
J
OINING
M
ETHODS
WARNING
T
O AVOID BODILY INJURY, FIRE OR EXPLOSION, SOLVENT CEMENTS MUST BE
KEPT AWAY FROM ALL IGNITION SOURCES (I.E., SPARKS, OPEN FLAMES, AND
EXCESSIVE HEAT) AS THEY ARE COMBUSTIBLE LIQUIDS.
A
VOID BREATHING
CEMENT VAPORS OR CONTACT WITH SKIN AND/OR EYES.
Two- or three-inch nominal diameter PVC Schedule 40 pipe meet-
ing ASTM D1785, PVC primer meeting ASTM F656, and PVC sol-
vent cement meeting ASTM D2564 specifications must be used.
Fittings must be DWV type fittings meeting ASTM D2665 and ASTM
D3311. Carefully follow the manufacturer’s instructions for cutting,
cleaning, and solvent cementing of PVC.
As an alternative to PVC pipe, primer, solvent cement, and fittings,
ABS materials which are in compliance with the following specifica-
tions may be used. Two-or-three-inch ABS Schedule 40 pipe must
meet ASTM D1527 and, if used in Canada, must be CSA listed.
Solvent cement for ABS to ABS joints must meet ASTM D2235 and,
if used in Canada, must be CSA listed. The solvent cement for the
PVC to ABS transition joint must meet ASTM D3138. Fittings must
be DWV type fittings meeting ASTM D2661 and ASTM D3311 and,
if used in Canada, must be CSA listed. Carefully follow the pipe
manufacturers’ instructions for cutting, cleaning, and solvent ce-
menting PVC and/or ABS.
All 90° elbows must be medium radius (1/4 bend DWV) or long
radius (Long sweep 1/4 bend DWV) types conforming to ASTM
D3311. A medium radius (1/4 bend DWV) elbow measures 3 1/16”
minimum from the plane of one opening to the centerline of the
other opening for 2” diameter pipe, and 4 9/16” minimum for 3”
pipe.
P
ROPER
V
ENT
/F
LUE
AND
C
OMBUSTION
A
IR
P
IPING
P
RACTICES
Adhere to these instructions to ensure safe and proper furnace per-
formance. The length, diameter, and number of elbows of the vent/
flue pipe and combustion air pipe (when applicable) affects the per-
formance of the furnace and must be carefully sized. All piping
must be installed in accordance with local codes and these instruc-
tions.
Piping must be adequately secured and supported to prohibit sag-
ging, joint separation, and/or detachment from the furnace. Hori-
zontal runs of vent/flue piping must be supported every three feet
and must maintain a 1/4 inch per foot downward slope, back to-
wards the furnace, to properly return condensate to the furnace’s
drain system. Allowances should be made for minor expansion
and contraction due to temperature variations. For this reason,
particular care must be taken to secure piping when a long run is
followed by a short offset of less than 40 inches.
Precautions should be taken to prevent condensate from freezing
inside the vent/flue pipe and/or at the vent/flue pipe termination. All
vent/flue piping exposed to freezing temperatures below 35°F for
extended periods of time must be insulated with 1/2” thick closed
cell foam. Also all vent/flue piping exposed outdoors in excess of
the terminations shown in this manual (or in unheated areas) must
be insulated with 1/2” thick closed cell foam. Inspect piping for
leaks prior to installing insulation.
