5
099435
FRESH AIR
FOR
COMBUSTION
AND
VENTILATION
WARNING ICON
G 001
WARNING
This heater must have fresh air for proper operation. If not, poor
fuel combustion could result. Read the following instructions to
insure proper fresh air for this and other fuel-burning appliances
in your home.
Today’s homes are built more energy efficient than ever. New materials, increased
insulation, and new construction methods help reduce heat loss in homes. Home
owners weather strip and caulk around windows and doors to keep the cold air out
and the warm air in. During heating months, home owners want their homes as
airtight as possible.
While it is good to make your home energy efficient, your home needs to breathe.
Fresh air must enter your home. All fuel-burning appliances need fresh air for
proper combustion and ventilation.
Exhaust fans, fireplaces, clothes dryers, and fuel burning appliances draw air from
the house to operate. You must provide adequate fresh air for these appliances.
This will insure proper venting of vented fuel-burning appliances.
PRODUCING ADEQUATE VENTILATION
All spaces in homes fall into one of the three following ventilation classifications:
1. Unusually Tight Contruction; 2. Unconfined Space; 3. Confined Space.
The information on pages 5 through 8 will help you classify your space and provide
adequate ventilation.
Unusually Tight Construction
The air that leaks around doors and windows may provide enough fresh air for
combustion and ventilation. However, in buildings of unusually tight construction,
you must provide additional fresh air.
Unusually tight construction is defined as construction where:
a. walls and ceilings exposed to the outside atmosphere have a continu-
ous water vapor retarder with a rating of one perm or less with open-
ings gasketed or sealed
and
b. weather stripping has been added on openable windows and doors
and
c. caulking or sealants are applied to areas such as joints around window
and door frames, between sole plates and floors, between wall-ceiling
joints, between wall panels, at penetrations for plumbing, electrical, and
gas lines, and at other openings.
If your home meets all of the three criteria above, you must provide addi-
tional fresh air. See
Ventilation Air From Outdoors, page 8.
If your home does not meet all of the three criteria above, continue reading.
Unconfined Space
An unconfined space has a minimum air volume of 50 cubic feet for each 1000
BTU/Hr input rating of all appliances in the space (cubic feet equals length x
width x height of space). Include adjoining rooms only if there are doorless
passageways or ventilation grills between the rooms.
Confined Space
A confined space has an air volume of less than 50 cubic feet for each 1000
BTU/Hr input rating of all appliances in the space (cubic feet equals length x
width x height of space). Include adjoining rooms only if there are doorless
passageways or ventilation grills between the rooms.
Continued
