3. Add the Btu/Hr of all fuel burning appliances in the space.

 

 

 

 

 

 

 

Vent-free heater

 

 

 

 

 

 

 

 

 

 

Btu/Hr

 

 

 

 

 

 

 

Gas water heater*

 

 

 

 

 

 

 

 

 

 

Btu/Hr

Example:

 

 

 

 

 

Gas furnace

 

 

 

 

 

 

 

 

 

 

Btu/Hr

Gas

water

heater

 

40,000

Btu/Hr

Vented gas heater

 

 

 

 

 

 

 

 

 

 

Btu/Hr

Vent

free

heater

+

20,000

Btu/Hr

Gas Fireplace logs

 

 

 

 

 

 

 

 

 

 

Btu/Hr

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Total

 

 

=

60,000

Btu/Hr

Other gas appliances* +

 

 

 

 

 

 

 

 

 

 

Btu/Hr

 

 

 

 

 

 

 

Total

=

 

 

 

 

 

 

 

 

Btu/Hr

 

 

 

 

 

 

 

*Do not include direct-vent

gas appliances. Direct-vent

draws

combustion

air

from the

outdoors and

vents to the outdoors.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

4.Compare the maximum Btu/Hr the space can support with the actual amount of Btu/Hr used. Btu/Hr (maximum the space can support)

Btu/Hr (actual amount of Btu/Hr used)

Example : 51,200 Btu/Hr(maximum the space can support) 60,000 Btu/Hr(actual amount of Btu/Hr used)

The space in the above example is a confined space because the actual Btu/Hr used is more than the

maximum Btu/Hr the space can support.

 

 

 

 

You must provide additional fresh air. Your

options are

as

follows:

A. Rework worksheet, adding the space of

an adjoining

room. If the extra space provides an unconfined

space, remove door to

adjoining room or

add ventilation

grills

between rooms. See Ventilation Air From

Inside Building, page 5.

 

 

 

 

 

B. Vent room directly to

the outdoors. See

Ventilation Air From Outdoors, page 6 .

C. Install a lower Btu/Hr

heater, 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.

VENTILATION AIR

Ventilation Air From Inside Building This fresh air would come from an adjoining unconfined space. When ventilating to an adjoining unconfined space, you must provide two permanent openings: one within 12" of the ceiling and one within 12" of the floor on the wall connecting the two spaces (see options 1 and 2, Figure 2). You can also remove door into adjoining room (see option 3, Figure 2). Follow the National Fuel Gas Code NFPA 54/ANS Z223.1. Section 5.3, Air for Combustion and Ventilation for required size of ventilation grills or ducts

WARNING: Rework worksheet, add- ing the space of the adjoining unconfined space. The combined spaces must have enough fresh air to supply all appliances in both spaces.

Figure 2 -Ventilation Air from Inside Building

5

Page 5
Image 5
PYLE Audio MN300HGA installation manual Ventilation Air From Outdoors, Ventilation AIR