Installation and Owner's Manual

PREPARING FOR INSTALLATION

AIR FOR COMBUSTION AND VENTILATION

WARNING: This heater shall not be installed in a room or space unless the required volume

of indoor combustion air is provided by the method described in the Nation Fuel Gas Code, ANSI

Z223.1/NFPA 54, the International Fuel Gas Code, or applicable local codes.

PRODUCING ADEQUATE VENTILATION

All spaces in homes fall into one of the three following ventilation classications:

1. Unusually Tight Construction

2. Unconned Space

3. Conned Space

The information on pages 9 through 11 will help you classify your space and provide adequate ventilation.

Conned and Unconned Space

A conned space as a space whose volume is less than 50 cu. ft. per 1,000 BTU/hr (4.8 m^3 per kw)

of the aggregate input rating of all appliances installed in that space and an unconning space as a

space whose volume is not less than 50 cu. ft. per 1,000 BTU/hr (4.8 m^3 per kw) of the aggregate

input rating of all appliances installed in that space. Rooms connecting directly with the space in

which the appliances are installed*, through openings not furnished with doors, are considered a

part of the unconned space.

This heater shall not be installed in a conned space or unusually tight construction unless provisions

are provided for adequate combustion and ventilation air.

* Adjoining rooms are connecting only if there are doorless passageways or ventilation

grills between them.

Unusually Tight Construction

The air that leaks around doors and windows may provide enough fresh air for combustion and venti-

lation. However, in buildings of unusually tight construction, you must provide additional

fresh air.

Unusually tight construction is dened as construction where:

a) walls and ceilings exposed to the outside atmosphere have a continuous water vapor retarder

with a rating of one perm (6x10-11kg per pa-sec-m2) or less with openings gasketed or sealed

and

b) weather stripping has been added on windows that can be opened and on doors and

c) caulking or sealants are applied to areas such as joints around window and door frames,

between sole plates and oors, 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 10). If your home does not meet all of the

three criteria above, proceed to “Determining Fresh-Air Flow For Heater Location”.