MHSC SB50HB Installation, Operation And Maintenance Manual page 25

OuTSIde COMBuSTION aIr preCauTIONS & reCOMMeNdaTIONS
OuTSIde COMBuSTION aIr reCOMMeNdaTIONS
1. Extremely long runs and numerous turns in the duct leading from the fireplace to the combustion
air assembly should be avoided. These conditions will increase the resistance to the free flow of air
through the duct. Refer to Figures 3, 28 and 29 for methods of installing the outside air for combustion
assemblies.
. The combustion air assembly should be located at an exterior location, which is not likely to be
accidentally blocked in any manner. The assembly should be located above the snow line to prevent
blockage by snow accumulation.
3. The combustion air inlet assembly should never be mounted in a garage or storage area where
combustible fumes such as gasoline might be drawn into the fireplace.
4. Combustion air can be drawn from the crawl space under a house when an adequate supply of air
is provided by open ventilation.
5. Do not take combustion air from attic space or garage space.
6" Diameter Hole
Duct
Extending
3" min.
FP1904
AK4 Inlet Air Vent
Combustion air assembly
Figure 29
87D0058
(continued)
Screw
Nail
Holes
Screws
Outside Air Control
Lever
(Lift to Open, Pull
Down to Close)
SB50HB Series Woodburning Fireplace
FP3
5