Monessen Hearth mhsc eyf24 User Manual

7

Adhere to all local codes or, in their absence, the latest edition of THE NATIONAL FUEL GAS CODE ANSI Z223.1 or 
NFPA54 which can be obtained from…

1430 Broadway

New York, NY 10018

or

Batterymarch Park

Quincy, MA 02269

This heater shall not be installed in a confined space or unusually tight construction unless provisions are provided for ad-
equate combustion and ventilation air.
The National Fuel Gas Code, (ANSI Z223.1), 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. An uncon-

fined space is defined 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.

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 1 perm 

(6 x 10

11

 kg per-pa-sec-m

2

) or less with openings gasketed or sealed, and

b)  weather striping has been added on openable windows and doors, and
c)   caulking or sealant are applied to areas such as joints around windows and door frames; between sole plates and doors; 

between wall-ceiling joints; between wall panels; at penetrations for plumbing, electrical, and gas lines; and at other 
openings.