VENT-FREE PROPANE/LP HEATER

AIR FOR

COMBUSTION AND

VENTILATION

Continued

DETERMINING FRESH-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

Example:

 

 

 

 

Gas furnace

_____________________ Btu/Hr

Gas water heater

 

 

30,000

Btu/Hr

Vented gas heater

_____________________ Btu/Hr

Vent-free heater

+

30,000

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 adjoin- ing 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 7.

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.

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 adequate combustion and ventilation air by one of the methods described in the National Fuel Gas Code, ANS Z223.1, Section 5.3 or applicable local codes.

For more information, visit www.desatech.com

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Desa RFP30TA installation manual AIR for Combustion Ventilation, Determining FRESH-AIR Flow for Heater Location
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RFP30TA specifications

The Desa RFP30TA is a standout heating solution designed for residential and light commercial spaces. With a powerful output and a variety of features, this gas-fired heater is built to provide efficient warmth while ensuring safety and convenience for users.

One of the main features of the Desa RFP30TA is its impressive heating capacity. With an output of up to 30,000 BTUs, it is capable of warming spaces of approximately 1,000 square feet, making it suitable for larger rooms or open areas. This makes it an excellent choice for basements, workshops, or other spaces that require effective heating during colder months.

The heater is designed with efficiency in mind. It boasts a high Annual Fuel Utilization Efficiency (AFUE) rating, which translates to lower energy bills and reduced greenhouse gas emissions. Its innovative design ensures that more of the fuel is converted into usable heat, which is not only economical for users but also beneficial for the environment.

As for technology, the Desa RFP30TA incorporates advanced safety features that prioritize user protection. The unit is equipped with a built-in safety shut-off system that automatically turns off the heater if it detects any irregularities in operation. Additionally, it utilizes a reliable thermocouple that monitors flame presence, ensuring that the heater operates safely at all times.

Another characteristic that sets the Desa RFP30TA apart is its versatility in installation. The heater comes with options for both vented and unvented installations, allowing users to choose the best setup for their specific needs. This flexibility means that the unit can be installed in a variety of locations, whether it’s vented to the outdoors or designed for indoor use without the need for a flue.

Furthermore, the Desa RFP30TA is designed with user-friendly controls. The adjustable thermostat allows for precise temperature management, enabling users to maintain their desired comfort level. This feature, combined with the unit's robust build quality, makes it a reliable option for long-term use.

In summary, the Desa RFP30TA is an efficient and powerful heating solution that combines modern technology with user-centric design. With its impressive output, safety features, installation flexibility, and user-friendly controls, it stands as a top choice for those looking for an effective heating solution for their spaces.
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