22 • Residen al Gas Tankless Water Heater Use and Care Guide
INSTALLATION
Table 7: Plas c Vent Pipe Table
Item
Material
United States
Canada
Exhaust pipe and
Fi ngs
Schedule 40 PVC
ANSI/ASTM D1785
ULC S636 Cer
fi
ed
Materials Only
PVC-DWV
ANSI/ASTM D2665
Schedule 40 CPVC
ANSI/ASTM F441
Schedule 40 ABS-DWV
ANSI/ASTM D2661
Polypropylene
UL-1738
Pipe Cement/Primer
PVC
ANSI/ASTM D2564
CPVC
ANSI/ASTM F493
ABS
ANSI/ASTM D2235
Use of cellular core PVC (ASTM F891), cellular core CPVC, or Radel® (polyphenylsulfone) in non-metallic ven ng systems is prohibited.
Covering non-metallic vent pipe and
fi
ngs with thermal insula on is prohibited.
NOTE: Approved vent and air intake Polypropylene vent materials: Centrotherm InnoFlue® Single Wall Vent System
Table 8: Vent Pipe Lengths
No. of
Elbows
Max. Ver cal or Horizontal (Total) Vent Length
2" ven ng
3" ven ng
0
75 (22.9 m)
150 (45.7 m)
1
70 (21.3 m)
145 (44.2 m)
2
65 (19.8 m)
140 (42.7 m)
3
60 (18.3 m)
135 (41.1 m)
4
55 (16.8 m)
130 (39.6 m)
5
50 (15.2 m)
125 (38.1 m)
Excludes vent terminators, termina on elbows, or rain caps.
For details on the vent connec on, refer to “Installing the Vent Pipe.” on page 23.
For each 90 degree elbow added, deduct 5 . 45 degree elbows count as 2.5 feet.
