Bradford White M-2-TW-75T6SX User Manual
Page 25
 
25
Combustion Air Supply 
 
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 venting, 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
m
3
/0.29 kw-hr).
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.