35
VENTING NOTES FOR FIGURES 34--46
1. For common vent, vent connector sizing and vent material: United States----use the NFGC.
2. Immediately increase to 5--in. or 6--in. (127 or 152 mm) vent connector outside furnace casing when 5--in. (127 mm) vent connector is
required, refer to Note 1 above.
3. Side outlet vent for upflow and downflow installations must use Type B vent immediately after exiting the furnace, except when the
factory--approved Downflow Vent Guard Kit is used in the downflow position. See Table 16 for accessory listing.
4. Type--B vent where required, refer to Note 1 above.
5. A 4--in. (102 mm) single--wall (26 ga. min.) vent must be used inside furnace casing and when the factory--approved Downflow Vent
Guard Kit is used external to the furnace. See Table 16 for accessory listing.
6. Accessory Downflow Vent Guard Kit required in downflow installations with lower vent configuration. See Table 16 for accessory
listing.
7. Chimney Adapter Kit may be required for exterior masonry chimney applications. Refer to Chimney Adapter Kit for sizing and
complete application details. See Table 16 for accessory listing.
8. Secure vent connector to furnace elbow with (2) corrosion--resistant sheet metal screws, spaced approximately 180
_
apart.
9. Secure all other single wall vent connector joints with (3) corrosion resistant screws spaced approximately 120
_
apart. Secure Type--B
vent connectors per vent connector manufacturer’s recommendations.
10. The total height of the vent and connector shall be at least 7 ft. (2 M) (for the 154,000 Btuh gas input rate model when installed in a
downflow application with furnace elbow turned to left side with the connector elbow outside furnace casing pointing upward. (See
Fig. 38 .)
Caution!! For the following applications, use the minimum vertical vent heights as specified below.
For all other applications, follow exclusively the National Fuel Gas Code.
FURNACE
ORIENTATION
VENT
ORIENTATION
FURNACE
INPUT (BTUH/HR)
MINIMUM VENT
DIAMETER
IN. (mm)*
MINIMUM VERTICAL VENT
HEIGHT
FT. (M)**
Downflow
Vent elbow left, then
up Fig.
36
154,000
132,000
110,000(036/---12 only)
5 (127)
12 (3.6)
Horizontal Left
Vent elbow right,
then up Fig.
39
154,000
132,000
5 (127)
7 (.65)
Horizontal Left
Vent Elbow up
Fig.40
154,000
132,000
5 (127)
7 (,65)
Horizontal Left
Vent elbow right Fig.
41
154,000
5 (127)
7 (.65)
Downflow
Vent elbow up then
left Fig.
34
110,000
(036/---12 only)
5 (127)
10 (3.0)
Downflow
Vent elbow up, then
right Fig.
37
110,000
(036/---12 only)
5 (127)
10 (3.0)
* 4 in. (102 mm) inside casing or vent guard
** Including 4 in. (102 mm) vent section (s)
NOTE:
All vent configurations must also meet National Fuel Gas Code venting requirements NFGC
58D
L