Installation & Operation Manual
5Vertical direct venting (continued)
Vent/air termination – vertical
Prepare roof 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:
•5½ inch hole (140 mm) hole for 4 inch (102 mm) vent pipe
•7½ inch hole (191 mm) hole for 6 inch (152 mm) vent pipe
b.Insert a galvanized metal thimble in the vent pipe hole (when required by local codes).
3.Space the air and vent holes to provide the minimum spacing shown in FIG.’s
4.Follow all local codes for isolation of vent pipe when passing through floors, ceilings, and roofs.
5.Provide flashing and sealing boots sized for the vent pipe and air pipe.
Termination and fittings
1.Prepare the vent termination coupling and the air termination elbow (FIG.’s
2.The air piping must terminate in a
3.The vent piping must terminate in an
4.Maintain the required dimensions of the finished termination piping as shown in FIG.’s
5.Do not extend exposed vent pipe outside of building more than shown in this document. Condensate could freeze and block vent pipe.
Multiple vent/air terminations
1.When terminating multiple Knight XL boilers, terminate each vent/air connection as described in this manual (FIG.
Terminate all vent pipes at the same height WARNING and all air pipes at the same height to
avoid recirculation of flue products and the possibility of severe personal injury, death, or substantial property damage.
2. Place roof penetrations to obtain minimum clearance of 12 inches (305 mm) between edge of air intake elbow and adjacent vent pipe of another boiler for U.S. installations (see FIG.
3. The air inlet of a Knight XL 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.
Figure
12" (305 MM) MINIMUM VERTICALLY FROM VENT OUTLET TO ANY AIR INLET
| VENT |
| AIR |
| 12" (305 MM) MINIMUM FROM EDGE |
VENT | OF AIR INTAKE PIPE TO ADJACENT |
AIR | VENT PIPE FROM ANOTHER BOILER |
|
Figure
VENT
VENT
12" (305 MM) MINIMUM VERTICALLY FROM VENT OUTLET TO ANY AIR INLET
AIR
AIR
31