14
Page
-Exhaust vent (ABS, PVC, CPVC, or polypropylene vent)-
This appliance can be vented
with
ABS,
PVC,
CPVC,
or
polypropylene
(temperature
rated
up
to
at
least 149 °F).
Vent material
certified
to ULC S636 standards is recommended in the USA.
In Canada,
plas
tic
ven
ting mu
s
t be certified
to ULC S636 standards.
•
The maximum length of exhaust vent piping must not exceed 70
ft.
(21.3 m) for 3” ven
tin
g, which
depends on the eleva
tion
where the micro-boiler is installed, and 100
ft.
(30.5 m) for 4” ven
ting
(deducting
5
ft.
(1.5 m) for each elbow used in the ven
ting
system). Do not use more than 5
elbows. See the table below.
•
When the horizontal vent run exceeds 5
ft.
(1.5 m), support the vent run at 3
ft.
(0.9 m) intervals
with overhead hangers.
Item
Material
United States
Canada
Exhaust pipe and
Fi
ttings
Schedule 40 PVC
ANSI/ASTM D1785
ULC S636
Certified
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
NOTE: Do NOT Use Cellular Foam Core Pipe
Diameter
Max. No. of Elbows Max. V
erti
cal and Horizontal (Total) Vent Length
3 in. (76 mm)
5
70
ft.
(21.3 m)
4 in. (102 mm)
5
100
ft.
(30.5 m)
*For each elbow added, deduct 5
ft.
(1.5 m) from max. vent length.
No. of Elbows
Max. V
erti
cal or Horizontal (Total) Vent Length
3" ven
ting
4" ven
ting
Up to 3,000
ft
Up to 6,000
ft
Up to 10,100
ft
Up to 10,100
ft
0
70
ft.
(21.3 m)
40
ft.
(12.2 m)
25
ft.
(7.6 m)
100
ft.
(30.5 m)
1
65
ft.
(19.8 m)
35
ft.
(10.7 m)
20
ft.
(6.1 m)
95
ft.
(29.0 m)
2
60
ft.
(18.3 m)
30
ft.
(19.1 m)
15
ft.
(4.6 m)
90
ft.
(27.4 m)
5
45
ft.
(13.7 m)
N/A
N/A
75
ft.
(22.9 m)
Excludes vent terminators, termina
tion
elbows, or rain caps.
For details on the vent c
onnection,
refer to p. 15 and p. 16.