23
P40-R I&O Manual
IM120801
RD: AUG 2013
RL: 1D
V
ERTICAL
VENT
THROUGH
THE
ROOF
:
(Horizontal vent through side wall is on pages 20
-
21)
It is the sole responsibility of the installer to adhere to all current local codes and/or ANSI
Z223.1 / CSA.B149.1 latest editions for all venting requirements, and practices.
Refer to General Venting Requirements on page 19
Any horizontal portion of vent must be mini-
mum 26 gauge single wall type “C” vent
pipe of 4” (10 cm) diameter (seal all con-
nections); vertical portion of vent can be 4”
type “B” vent
When the vent pipe passes through a cold
or unheated area where the ambient tem-
perature is likely to result in condensation
of the flue gases, the vent pipe will be
type ‘B’ vent or insulated with a suitable
material as approved and specified by the
insulation manufacturer to withstand tem-
perature up to 460°F (238°C).
Use an approved ‘B-vent’ termination cap
as supplied by the manufacturer of the
listed ‘B-vent’.
Minimum length of a vertical roof vent:
Minimum 12 inch (1 ft; 30.5 cm) single
wall ‘C’ vent
Plus
one 90° “C” vent elbow
Plus
minimum 36 inch (3 ft; 91.4 cm)
double wall ‘B’ vent
Total minimum linear vent length of 48
inches (4 ft; 122 cm)
plus
one 90° ‘C’
elbow
Maximum length of a vertical roof vent:
Above minimum requirements must be met
A maximum of one 90° elbow (equivalent 5 ft)
plus
two 45° elbows (each equivalent to
2.5 ft) can be installed in a vertical vent system
Refer to local and national codes for maximum allowable venting
Approved
Cap
Approved
‘B’ Vent
24”
60 cm
12
9
If roof slope exceeds 9:12
consult NFPA-54 ANSI
Z223.1 or CSA-B149.1
FIGURE 12
Up
to
Minimum 12”
(30.5 cm)
‘C’ Vent
Minimum 36”
(91.5 cm)
‘B’ Vent
90° ‘C’ Vent
Elbow
‘C’ to ‘B’ Adapter
Thimble
FIGURE 13
