Desa Design Dynamics VTD-18N-BTB Owner's Operation And Installation Manual page 6

6
AIR FOR COMBUSTION AND VENTILATION
Ventilation Air (Cont.)
AIR FOR COMBUSTION AND
VENTILATION
Continued
the outdoors or spaces open to the outdoors. These spaces include
attics and crawl spaces. Follow the National Fuel Gas Code, ANSI
Z223.1/NFPA 54, Section 5.3, Air for Combustion and Ventilation
for required size of ven ti la tion grills or ducts.
IMPORTANT: Do not provide openings for inlet or outlet air into
attic if attic has a ther mo stat-controlled power vent. Heated air
entering the attic will activate the power vent.
Ventilation
Grills
Into Adjoining
Or
Room,
Remove
Option 1
Door into
Adjoining
Room,
Option
3
Figure 2 - Ventilation Air from Inside Building
12"
Ventilation Grills
Into Adjoining Room,
Option 2
12"
For more information, visit www.desatech.com
Outlet
Air
Outlet
Air
Inlet
Air
Inlet Air
Figure 3 - Ventilation Air from Outdoors
Ventilated
Attic
To Attic
To
Crawl
Space
Ventilated
Crawl Space
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