All vent pipes and air inlets must terminate
at the same height to avoid possibility
of severe personal injury, death, or
substantial property damage.
Multiple vent/air terminations
1. When terminating multiple boilers terminate each vent/
air connection as described in this manual (FIG. 4-5A).
2. Place wall penetrations to obtain minimum clearance
of 12 inches between edge of air inlet and adjacent vent
outlet, as shown in FIG. 4-5A for U.S. installations. For
Canadian installations, provide clearances required by
CSA B149.1 Installation Code.
3. The air inlet of a Noble Combi Boiler is part of a direct
vent connection. It is not classified as a forced air intake
with regard to spacing from adjacent boiler vents.
WARNING
Figure 4-5A Multiple Vent Terminations w/Field Supplied
Fittings (must also comply with Figure 4-1A)
Prepare wall penetrations
1. Air pipe penetration:
a. Cut a hole for the air pipe. Size the air pipe hole as
close as desired to the air pipe outside diameter.
2. Vent
pipe
penetration:
a. Cut a hole for the vent pipe. For either combustible
or noncombustible construction, size the vent pipe
hole with at least a 1/2 inch clearance around the vent
pipe outer diameter:
• 3½ inch hole for 2 inch vent pipe
• 4½ inch hole for 3 inch vent pipe
b. Insert a galvanized metal thimble in the vent pipe
hole as shown in FIG. 4-4A.
3. Use the sidewall termination plate as a template for
correct location of hole centers.
4. Follow all local codes for isolation of vent pipe when
passing through floors or walls.
5. Seal exterior openings thoroughly with exterior caulk.
AIR PIPING
ELBOW
BIRD SCREEN
ELBOW
BIRD SCREEN
SIDEWALL
TERMINATION PLATE
GALVANIZED
THIMBLE
VENT PIPING
Figure 4-4A Sidewall Termination Assembly w/Field
Supplied Fittings
4
Sidewall direct venting
(continued)
23
12" MIN. BETWEEN EDGE OF AIR
INLET AND ADJACENT VENT OUTLET
VENT / AIR
TERMINATION
VENT
AIR
Figure 4-5B Alternate Multiple Vent Terminations (must
also comply with Figure 4-1B)
Installation & Service Manual
F I R E T U B E C O M B I
™
