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6
101968
AIR FOR
COMBUSTION
AND
VENTILATION
WARNING ICON
G 001
WARNING
This fireplace 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. Fresh air enters the home through and around doors
and windows. This may provide enough fresh air for combustion and ventilation. 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.
PROVIDING ADEQUATE VENTILATION
The following are excerpts from the National Fuel Gas Code NFPA 54/ANSI Z223.1,
Section 5.3, Air for Combustion and Ventilation.
All spaces in homes fall into one of the three following ventilation classifications:
1. Unusually Tight Construction; 2. Unconfined Space; 3. Confined Space.
The information on pages 6 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 com-
bustion 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 additional
fresh air. See
Ventilation Air From Outdoors
, page 8
.
If your home does not meet all of the three criteria above, proceed to page 7.
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.
If the Btu per 50 cubic feet is less than 1000 Btu/Hr, then the fresh air will be
provided by the natural air flow into the house.
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.
Summary of Contents for UNVENTED (VENT-FREE) NATURAL GAS FIREPLACE
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