Install Instructions

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9. Locate the combustion air terminal on
the same face of the building as the vent
termination to prevent nuisance boiler
shutdowns.
10. If the vent passes through interior spaces
in oors above the boiler room, enclose the
vent with material having a re resistance
rating at least equal to the rating of the
adjoining oor or ceiling. Maintain minimum
clearances to combustible materials
between the enclosure and the vent.
11. Use appropriate designed thimbles when
passing through combustible walls (thimble
use is optional for noncombustible walls).
Ensure thimble is sealed to prevent moisture
from entering structure.
Planning Vertical Installations –
1. Install re stop where vent and air intake
passes through oors, ceilings or framed
Figure B-2: Approved Terminal Locations
walls. The re stop must close the opening
between the vent and/or air intake pipe and
the structure.
2. Size roof opening to allow easy insertion of
vent and air intake piping to allow proper
installation of ashing and storm collar to
prevent moisture from entering the structure
3. Use appropriately designed vent ashing
when passing through roofs. Follow ashing
manufacturers’ instructions for procedures.
4. Ensure there is a weather-tight seal between
the vent and/or air intake piping were it
penetrates the storm collar and roof ashing.
5. Extend the vent and air intake pipe to
maintain a minimum vertical and horizontal
distance of twelve (12) inches from the roof
surface. Allow additional vertical distance
for expected snow accumulation. Brace as
required.
APPENDIX B2 – Direct Venting (continued)