Vanguard Heating VS24PR - Manual (Page 5)

5
103448
WARNING
This heater shall not be installed in a confined space unless provisions are provided for
adequate combustion and ventilation air. 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.
AIR FOR
COMBUSTION
AND
VENTILATION
PROVIDING ADEQUATE VENTILATION
The following is exerpts from 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 Contruction
2. Unconfined Space
3. Confined Space
The information on pages 5 through 7 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 ventila-
tion. 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 continuous water vapor
retarder with a rating of one perm (6x10 -11 per pa-sec-m 2 ) or less with openings
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 7 .
If your home does not meet all of the three criteria above, continue reading.
Confined Unconfined Space
The National Fuel Gas Code (ANSIZ223.1, 1992 Section 5.3) defines a confined space as a space whose
volume is less than 50 cubic feet per 1,000 Btu per hour (4.8 m
3 per kw) of the aggregate input rating of
all appliances installed in that space and an unconfined space as a space whose volume is not less than 50
cubic feet per 1,000 Btu per hour (4.8 m
3 per kw) of the aggregate input rating of all appliances installed
in that space. Rooms communicating directly with the space in which the appliances are installed*,
through openings not furnished with doors, are considered a part of the unconfined space.
* Adjoining rooms are communicating only if there are doorless passageways or ventilation grills between
them.
Continued