Radiant Heating and Cooling
ASHRAE Technical Committee 6.5

Scope of TC 6.5

TC 6.5 is concerned with all types of sensible radiant space heating and cooling systems. Typical applications are high or medium-temperature radiant elements, spot, or total area radiant heating panels or thermally active slabs for heating and cooling.


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HVAC Sys & Equip: Panel Htg & Cooling
This chapter covers temperature-controlled surfaces that are the primary source of sensible heating and cooling in the conditioned space. For snow-melting and freeze-protection applications, see Chapter 51 of the 2011 ASHRAE Handbook—HVAC Applications. Chapter 16 covers high-temperature panels over 300°F (150°C), which maybe energized by gas, electricity, or high-temperature water.

HVAC Sys & Equip: Infrared Radiant Htg
Infrared radiant heating principles discussed in this chapter apply to equipment with thermal radiation source temperatures ranging from 300 to 5000°F (150 to 2760°C). (Equipment with source temperatures starting from below the indoor air temperature to 300°F [150°C] is classified as panel heating and cooling equipment, discussed in Chapter 6.)

HVAC Sys & Equip: Res. In-Space Htg
In-space heating equipment differs from central heating in that fuel is converted to heat in the space to be heated. In-space heaters may be either permanently installed or portable and may transfer heat by a combination of radiation, natural convection, and forced convection. The energy source may be liquid, solid, gaseous, or electric.

HVAC Sys & Equip: Snow Melting and Freeze Protection
This chapter covers three types of snow-melting and freeze protection systems: (1) hot fluid circulated in slab-embedded pipes (hydronic); (2) embedded electric heater cables or wire; and (3) overhead high-intensity infrared radiant heating. Detailed information about slab heating can be found in Chapter 6 of the 2012 ASHRAE Handbook—HVAC Systems and Equipment. More information about infrared heating can be found in Chapter 16 of the same volume.

HVAC Sys & Equip: Radiant Heating and Cooling
Radiant heating and cooling applications are classified as panel heating or cooling if the panel surface temperature is below 300°F (150°C), and as low-, medium-, or high-intensity radiant heating if the surface or source temperature exceeds 300°F (150°C). In thermal radiation, heat is transferred by electromagnetic waves that travel in straight lines and can be reflected. Thermal radiation principally occurs between surfaces or between a source and a surface. In a conditioned space, air is not heated or cooled in this process. Because of these characteristics, radiant systems are effective for both spot heating and space heating or cooling requirements for an entire building.

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 ASHRAE writes standards for the purpose of establishing consensus for: 1) methods of test for use in commerce and 2) performance criteria for use as facilitators with which to guide the industry. ASHRAE publishes the following three types of voluntary consensus standards: Method of Measurement or Test (MOT), Standard Design and Standard Practice. ASHRAE does not write rating standards unless a suitable rating standard will not otherwise be available. ASHRAE is accredited by the American National Standards Institute (ANSI) and follows ANSI's requirements for due process and standards development. Standards may be purchased at the ASHRAE Bookstore.

TC 6.5 is responsible for:
ANSI/ASHRAE Standard 138: Method of Testing for Rating Ceiling Panels for Sensible Heating and Cooling

Other Activities

TIP: If MTG involvement add here otherwise leave blank.

Cold Climate Design Guide

This MTG will coordinate TC/TG/TRG technical activities to help support the technical basis, development, and publication of a “Cold Climate Design Guide” in conjunction with REHVA and SCANVAC. Responsibilities include the development of supporting research, presentations, and content for the “Cold Climate Design Guide” special publication.


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