Bradford White TW4-75S-76B-3X - Manual (Page 21)

21
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!
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 water heater.
When an exhaust fan is installed in the same room with a water 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).
IMPORTANT
The flow of combustion and ventilating air must not be obstructed.