Combustion Air Supply
WARNING
Liquefied petroleum gases/propane gas are heavier than air and will remain at floor level if there is a leak. Basements, crawl spaces, closets and areas below ground level will serve as pockets for accumulation of leaking gas. Before lighting, smell all around the appliance area for gas. Be sure to smell next to the floor.
IF YOU SMELL GAS:
∙Do not try to light any appliance.
∙Do not touch any electric switch; do not use any telephone in your building.
∙Immediately call your gas supplier from a neighbor’s telephone. Follow the gas supplier’s instructions.
∙If you cannot reach your gas supplier, call the fire department.
DO NOT OPERATE APPLIANCE UNTIL LEAKAGE IS CORRECTED!
IMPORTANT
The flow of combustion and ventilating air must not be obstructed.
Provide adequate air for combustion and ventilation. An insufficient supply of air will cause recirculation of combustion products resulting in air contamination that may be hazardous to life. Such a condition often will result in a yellow, luminous burner flame, causing carbon build up or sooting of the combustion chamber, burners, and flue tubes with possible damage to the heater.
When an exhaust fan is installed in the same room with a heater, sufficient openings for air must be provided in the walls. Undersized openings will cause air to be drawn into the room through the chimney, causing recirculation of combustion products.
Unconfined Spaces
In unconfined spaces in buildings, infiltration may be adequate to provide air for combustion, ventilation, and dilution of flue gases. However, in buildings of tight construction (for example, weather stripping, heavily insulated, caulked, vapor barrier, etc.), additional air may need to be provided using the methods described under CONFINED SPACES: All Air From Outdoors or Specially Engineered Installations.
Confined Spaces
Confined spaces are spaces defined as having less than 50 ft.3/1000 BTU (1.4 m3/0.29
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