AIR FOR COMBUSTION AND VENTILATION

Continued

DETERMINING AIR FLOW FOR HEATER LOCATION

Determining if You Have a Confined or Unconfined Space

Use this worksheet to determine if you have a confined or unconfined space.

Space: Includes the room in which you will install heater plus any adjoining rooms with doorless passageways or ventilation grills between the rooms.

1. Determine the volume of the space (length x width x height).

Length x Width x Height = ___________________ cu. ft. (volume of space)

Example: Space size 20 ft. (length) x 16 ft. (width) x 8 ft. (ceiling height) = 2560 cu. ft. (volume of space)

If additional ventilation to adjoining room is supplied with grills or openings, add the volume of these rooms to the total volume of the space.

2.Divide the space volume by 50 cubic feet to determine the maximum Btu/Hr the space can support.

____________ (volume of space) ÷ 50 cu. ft. = (Maximum Btu/Hr the space can support)

Example: 2560 cu. ft. (volume of space) ÷ 50 cu. ft. = 51.2 or 51,200 (maximum Btu/Hr the space can support)

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

Vent-free heater

 

___________________ Btu/Hr

Gas water heater*

 

___________________ Btu/Hr

Gas furnace

 

 

___________________ Btu/Hr

Vented gas heater

 

___________________ Btu/Hr

Gas fireplace logs

 

___________________ Btu/Hr

Other gas appliances*

+ ___________________ Btu/Hr

Total

= ___________________ Btu/Hr

Example: Gas water heater

 

40,000

Btu/Hr

Vent-free heater

+

 

18,000

Btu/Hr

Total

=

58,000

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)

58,000

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 7.

B.Vent room directly to the outdoors. See Ventilation Air From Outdoors, page 8.

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.

6

101809

Page 5 Page 7
Page 6
Image 6
Desa VN2800BTB, CFN2800BTB installation manual AIR for Combustion and Ventilation, Determining AIR Flow for Heater Location
Page 5 Page 7

VN2800BTB, CFN2800BTB specifications

Desa CFN2800BTB and VN2800BTB stand as premium heating solutions in the contemporary market, delivering superior warmth and user-friendly features to enhance any living environment. These models are characterized by their advanced technology, ergonomic design, and energy efficiency, making them ideal for both residential and commercial spaces.

One of the standout features of the CFN2800BTB and VN2800BTB is their innovative infrared heating technology. Unlike traditional convection heaters that warm the air, these units emit infrared rays that directly heat objects and people in the room. This not only results in faster heating but also ensures a more consistent warmth, allowing users to enjoy a comfortable ambiance even in larger spaces.

Moreover, these models boast a compact and stylish design, making them versatile for various room aesthetics. Their sleek appearance ensures that they can seamlessly blend into any decor without being obtrusive. The lightweight construction also facilitates easy relocation, allowing users to position the heater where it is most needed.

Energy efficiency is a key characteristic of the CFN2800BTB and VN2800BTB. Both units are designed to provide maximum warmth with minimal energy consumption. They feature adjustable heat settings, allowing users to customize the heating level to their needs, which not only contributes to comfort but also helps in reducing electricity bills. The built-in thermostat ensures that the heater maintains a consistent temperature, further optimizing energy use.

Safety is another paramount concern with these models. They come equipped with multiple safety features, including overheat protection and tip-over switches, which automatically turn the heater off in case of an accidental fall or overheating. This ensures peace of mind for users, particularly in homes with pets and children.

In conclusion, the Desa CFN2800BTB and VN2800BTB are exemplary heating solutions that combine modern technology with safety and efficiency. Their infrared heating capability, stylish design, and focus on user comfort make them standout products in the competitive heating appliance market. Whether for personal use or as an ideal solution for larger spaces, these models promise reliability and superior performance.
Top Page Image Contents