Outdoor Air Through Two Horizontal Ducts; Outdoor Air Through Two Vertical Ducts; Air From Other Indoor Spaces - Lochinvar LTN07575 Instruction Manual

OUTDOOR AIR THROUGH TWO HORIZONTAL
DUCTS
FIGURE 13. FRESH AIR FROM TWO HORIZONTAL DUCTS
The confined space shall be provided with two permanent
horizontal ducts, one commencing within 12 inches (300
mm) of the top and one commencing within 12 inches
(300 mm) of the bottom of the enclosure. The horizontal
ducts shall communicate directly with the outdoors. See
.
Figure 13
Each duct opening shall have a minimum free area of 1
square inch per 2,000 Btu/hr (1100 mm
aggregate input rating of all appliances installed in the
enclosure.
When ducts are used, they shall be of the same cross
sectional area as the free area of the openings to which
they connect. The minimum dimension of rectangular air
ducts shall be not less than 3 inches.

OUTDOOR AIR THROUGH TWO VERTICAL DUCTS

The illustrations shown in this section of the manual are
a reference for the openings that provide fresh air into
confined spaces only.
DO NOT refer to these illustrations for the purpose of
vent installation. See
Venting
venting instructions.
per kW) of the
2
(page 19) for complete
FIGURE 14. FRESH AIR FROM TWO VERTICAL DUCTS
The confined space shall be provided with two permanent
vertical ducts, one commencing within 12 inches (300
mm) of the top and one commencing within 12 inches
(300 mm) of the bottom of the enclosure. The vertical
ducts shall communicate directly with the outdoors. See
.
Figure 14
Each duct opening shall have a minimum free area of 1
square inch per 4,000 Btu/hr (550 mm
aggregate input rating of all appliances installed in the
enclosure.
When ducts are used, they shall be of the same cross
sectional area as the free area of the openings to which
they connect. The minimum dimension of rectangular air
ducts shall be not less than 3 inches.

AIR FROM OTHER INDOOR SPACES

The confined space shall be provided with two permanent
openings, one commencing within 12 inches (300 mm) of
the top and one commencing within 12 inches (300 mm)
of the bottom of the enclosure. See
18
per kW) of the
2
.
Figure 15