AIR FOR COMBUSTION AND VENTILATION CONTINUED
B.Vent room directly to the outdoors. See Ventilation Air from Outdoors, page 10.
C.Install a lower BTU/Hr firebox, if lower BTU/Hr size makes room unconfined.
If the actual BTU/Hr used is less than the maximum BTU/Hr the space can support, the space is an unconfined space. You will need no additional fresh air ventilation.
WARNING
If the area in which the heater may be operated is smaller than that defined as an unconfined space or if the building is of unusually tight construction, provide ad- equate combustion and ventilation air by one of the methods described in the Na- tional Fuel Gas Code, ANSI Z223.1, Section 5.3 or applicable local codes.
VENTILATION AIR
Ventilation Air From Inside Building
This fresh air would come from an adjoining unconfined space. When ventilating to an ad- joining unconfined space, you must provide two permanent openings: one within 12" of the ceiling and one within 12" of the floor into adjoining room ( see options in Figure 1).
Follow the National Fuel Gas Code NFPA 54/ ANSI Z223.1, Section 5.3, Air for Combustion and Ventilation for required size of ventilation grills or ducts.
WARNING
Rework worksheet, adding the space of the adjoining unconfined space. The combined spaces must have enough fresh air to supply all appliances in both spaces.
VENTILATION GRILLS INTO
ADJOINING ROOM.
OPTION 2
VENTILATION GRILLS
INTO ADJOINING
ROOM.
OPTION 1
OR REMOVE DOOR INTO
ADJOINING ROOM.
OPTION 3
Figure 1 - Ventilation Air from Inside Building
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