Terminal Location
of a Power Vent System
The location of the terminal of a vent system
must comply with manufacturer’s instruc-tions,
NFPA 31 and the local authority having
jurisdiction.
Manufacturer’s instructions and local codes
generally require that (See Figure 4):
A. It must be at least 7' above grade when
located adjacent to a public walkway.
B. It must be at least 4' below, 4' horizontally
from, or 1' above any door, window or air inlet
into a building.
C. It must be at least 3' above any forced air
inlet located within 10'.
Figure 4
28 National Oilheat Research Alliance
D. The bottom of the terminal must be at
least 1' above finished grade or the anticipated
snow load.
E. It must not be mounted directly above or
within 3' horizontally from an oil tank vent or
gas meter (not shown).
F. It must be at least 3' from an inside corner
of an L shaped structure.
Vent risers are available for basement instal-lations
where a window well is used, or in
situations where the vent terminal cannot be
mounted to maintain the minimum clearance
above grade or the anticipated snow load.
Figure 5.