Air-to-Air Energy Recovery
ASHRAE Technical Committee 5.5

Scope of TC 5.5

TC 5.5 is concerned with air-to-air heat exchangers, their application and cost benefit relationship. It includes consideration of the needs and procedures for standardization and testing, rating and terminology applicable to air-to-air energy recovery.


The ASHRAE Handbook is published in a series of four volumes, one of which is revised each year, ensuring that no volume is older than four years.

The Handbook can be purchased at the ASHRAE Bookstore by clicking on this link.

This TC is responsible for the following chapter in the HVAC Systems & Equipment Volume

Air-to-Air Energy Recovery
Air-to-air energy recovery is the process of recovering heat or/and moisture between two airstreams at different temperatures and humidities. This process is important in maintaining acceptable indoor air quality (IAQ) while maintaining low energy costs and reducing overall energy consumption. This chapter describes various technologies for air-to-air energy recovery. Thermal and economic performance, maintenance, and related operational issues are presented, with emphasis on energy recovery for ventilation.

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Technical committees develop and sponsor technical sessions at the winter and annual conferences. Information about their future technical program is discussed at each TC meeting and at the TC’s Program Subcommittee meeting.



Technical Committees are responsible for identifying research topics, proposing research projects, selecting bidders, and monitoring research projects funded by ASHRAE. Information about their specific research program is discussed at each TC meeting and at the TC’s Research Subcommittee meeting.

This TC is cosponsoring the following research

TC 8.10, Mechanical Dehumidification Equipment and Heat Pipes; Co-sponsoring TCs: 1.12, Moisture Management in Buildings,   TC 5.5, Air-To-Air Energy Recovery & TC 8.12, Desiccant Dehumidification Equipment and Components

This design guide will help practicing HVAC engineers design dedicated outdoor-air systems that minimize energy use, maximize indoor environmental quality, and balance life-cycle cost with environmental impact.


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.

This TC is cognizant for the following standard

ANSI/ASHRAE Standard 84: Method of Testing Air-to-Air Heat/Energy Exchangers

Other Activities

TIP: If MTG involvement add here otherwise leave blank.




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