Absorption and Heat Operated Machines
ASHRAE Technical Committee 8.3

Scope of TC 8.3

TC 8.3 is concerned with the design, performance and application of equipment energized by a heat source and using a thermodynamic cycle to provide an air-conditioning, refrigerating or heating function; with the properties of absorbent solutions or special working fluids used in these cycles; and with components of the cycle requiring specific design characteristics.


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.

Fundamentals: Thermodynamics
Thermodynamics is the study of energy, its transformations, and its relation to states of matter. This chapter covers the application of thermodynamics to refrigeration cycles. The first part reviews the first and second laws of thermodynamics and presents methods for calculating thermodynamic properties. The second and third parts address compression and absorption refrigeration cycles, two common methods of thermal energy transfer.

Refrigeration: Absorption Cooling, Heating, and Refrigeration Equipment
This chapter surveys and summarizes the types of absorption equipment that are currently manufactured and/or commonly encountered. The equipment can be broadly categorized by whether it uses water or ammonia as refrigerant. The primary products in the water refrigerant category are large commercial chillers, which use lithium bromide (LiBr) as absorbent. There are three primary products in the ammonia refrigerant category: (1) domestic refrigerators, (2) residential chillers, and (3) large industrial refrigeration units. This chapter focuses on hardware (i.e., cycle implementation), not on cycle thermodynamics. Cycle thermodynamic descriptions and calculation procedures, along with a tabulation of the types of absorption working pairs and a glossary, are presented in Chapter 2 of the 2013 ASHRAE Handbook—Fundamentals.

Fundamentals: Refrigerants & Thermophysical Properties of Refrigerants

Ammonia/Water and Water/Lithium Bromide properties

Comment on the Handbook: ASHRAE welcomes your comments on the Handbook or a specific Handbook chapter.  To submit a comment about any aspect or part of the Handbook series, you can use the Handbook Comment Form.

Review a Handbook Chapter: To provide your feedback about a specific Handbook chapter, you can answer the brief survey questions on the Handbook Chapter Review Form.


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.

ASHRAE publishes papers and transactions from presentations at its conference events. In addition, ASHRAE records most of the seminar sessions from its conferences on DVD. These DVDs are ideal for use at chapter meetings, in university courses, or company lunch and learns. Products available from the most recent conference may be found here.

2020 Winter Meeting in Orlando:                                                                                                                                                      SEMINAR 69: Current Products and Development in Absorption and Heat Operated Machines                                            1. Residential Space and Water Heating with Gas Absorption Heat Pumps, by Chris Keinath
2. Restaurant Demonstration of Water and Space Heating with an Absorption Heat Pump Water Heater, by Chris Smith
3. A Thermal Compression Heat Pump for Complete Building HVAC, by David Parks                                                                      4. Gas Heat Pumps for Integrated Commercial Hot Water and Air Conditioning in Restaurants, by Isaac Mahderekal

2019 Summer Meeting in Kansas City:                                                                                                                                            SEMINAR 53: Novel Optimization Techniques for Water Heating Using Sorption Systems                                                    1. Comparison and Optimization of Absorption Heat Pumps vs Conventional Water Heaters , by Chris Keinath
2. Optimization of a Chemisorption Heat Pump with Buffer Tank for Residential Heating Applications , by Zhiyao Yang
3. Optimization Framework to Maximize Absorption Water Heater Energy Efficiency, by Kyle Gluesenkamp                                   

2019 Winter Meeting in Atlanta:                                                                                                                                                        SEMINAR 17: Building Integrated Renewable Fueled Natural Refrigeration Systems                                                              1. Biomass Power Production in Austria, by Douglas Davis
2. Waste Heat Driven Cooling and Heating Technologies, by Rajesh Dixit
3. Efficient Dehumidification using a Compact Membrane-based Ionic Liquid Absorption Cycle, by Saeed Moghaddam

2018 Summer Meeting in Houston:
SEMINAR 20:  The Future of CHP: Packaged Systems, Resilience and Microgrids
1. CHP Systems: Reducing Risk and Improving Design, Packaged Systems Under 10 MW, by Richard Sweetser
2. CHP and Resilience Planning, by Bruce Hedman
3. Resilient CHP Microgrid Design: Hospital Case Study, by Gearoid Foley
SEMINAR 28:  Using District Energy to Survive a Storm: Case Studies in Disaster Preparedness
1. Dealing with Hurricane Harvey Using the Resiliency of the District Energy System, by Bruce Flaniken
2. Wading Through Harvey at Houston Airports, by Eren Selcen
3. University of Texas at Austin: Disaster Preparedness using a Microgrid with CHP and District Energy, by Juan Ontiveros
SEMINAR 41:  The Future of Thermal Cooling to Support Resilient CHP Systems
1. Pinellas County Jail: Decoupled "CCHP" in the Sunshine State with Modern Absorption, by Douglas A. Davis
2. Busting the Myths of Absorption Cooling Technology, by Rajesh Dixit
3. Best Method to Utilize Heat of Trigeneration: Exergy Transfer Issues in Absorption Cooling, by Ongun Berk Kazanci

2018 Winter Meeting in Chicago:
SEMINAR 63:  Challenges in Heat and Mass Exchange for Absorption Systems
1.  Enhancing Heat and Mass Transfer in Absorbers Using Membrane-Constrained Flow and Laminar Mixers, by Saeed Moghaddam
2.  Absorbers for Industrial Ammonia Absorption Units, by G Anand
3.  Titanium Tubes - The New Normal of Modern Absorption Units, by Doug Davis

2017 Summer Meeting in Long Beach:
SEMINAR 11:  Absorption Heat Pump Applications:  Industrial, Space Heating, and Water Heating
1.  Real World Examples of Industrial Absorption heat Pumps:  Exotic Applications, Working Fluids and Cycles (multi-effect), by Jürgen Scharfe
2.  Case Studies from Around the World that Are Using Modern Absorption Heat Pumps to Save Energy and Water Resources on Planet Earth, by Douglas A. Davis
3.  Mass Markets in the US for Sorption Heating Appliances, by Kyle Gluesenkamp

2017 Winter Meeting in Las Vegas:
SEMINAR 18: Thermally Driven Devices are Heating Up:  Emerging International Field Studies and Standards for Residential Fuel-Fired Sorption Heat Pumps
1.  Practical Experience of Field Testing Residential and Light Commercial Gas Absorption Heat Pumps, by Axel Albers
2.  Field Testing of Residential Gas Absorption Storage Water Heaters, by Paul Glanville
3.  Existing and Emerging International Standards for Evaluation of Fuel-Fired Sorption Heat Pumps, by Ivan Malenkovic
4.  Multi-Laboratory Round-Robin Testing of Commercialized Sorption Heat Pumps for Residential Space Heating, by Patizia Melograno
SEMINAR 65:  Impacts of Technology and Energy Markets to the Performance of Absorption Economics
1.  Hybrid Membrane-Based Ionic Liquid Absorption cycle for Water Heating, Dehumidification and Cooling, by Saeed Moghaddam
2.  Solar Thermal HEAT Pump/Chiller Debut, by Donald Erickson
3.  Absorption Systems Economics, by Ersin Gercek

2016 Summer Meeting in St. Louis:
Seminar 5:  Innovative Absorption System Applications for Both Heating and Cooling
1.  Practical Application of an Absorption Heat Pump to Commercial Water Heating, by Patrick Geoghegan
2.  Using Double and Triple Lift Single Stage Absorption to Save Energy, by Douglas Davis
3.  Absorption Heat Pumps for District Heating Applications, by Rajesh Sinha

2016 Winter Meeting in Orlando:
Seminar 29:  Modern Absorption Systems and Application for Both Cooling and Heating
1. Modern Commercial/Industrial Absorption Capabilities as Showcased in a BIG BOX Retail Store Application, by Doug Davis
2. Lithium-Bromide Water Absorption Heat Pumps for Heating Applications, by Rajesh Dixit

2015 Winter Meeting in Chicago:
Seminar 1: An Update on Energy Efficiency Analysis using ABSIM Absorption Simulator, Triple Duty Chillers and Type 2 Absorption Heat Pumps
1. "Type II Absorption Heat Pumps and Triple Effect Absorption Chillers" by Piyush Patel
2. "ABSIM: Modular and Flexible Simulation of Absorption Systems in Closed and Open Cycles" by Gershon Grossman

2014 Summer Meeting in Seattle:
Seminar 48: Successfully Applying Sorption Technologies for Fun and Profit
1. "Gas-fired Heat Pump Water Heaters" by Kyle Gluesenkamp
2. "Design Considerations for Ammonia-Water Binary System Equipment for Commercial Manufacturers"
by Samuel Leggett

2013 Summer Meeting in Denver:
Special Session 6: Workshop: Cutting Edge Absorption and Adsorption Cooling Technologies in Cogeneration and Trigeneration
1. "Waste Heat Recovery Using Absorption Chiller in LNG Plant With CO2 Capturing Plant"
by Abdullah Alabdalkarem, Yunho Hwang, Reinhard Radermacher
2. "Separate Sensible and Latent Cooling for Trigeneration" by Kyle Gluesenkamp, Yunho Hwang, Reinhard Radermacher
3. "Solar Combined Heat Power and Cooling or Solar Trigeneration" by Rajesh Dixit, Andrea Gains-Germain

 2013 Winter Meeting in Dallas:
Seminar 58: Leading Edge Advances in Absorption Cooling Technologies
1. "Ionic Fluid Design for Absorption Heat Pump Applications" by Omar Abdelaziz
2. "New Generation Membrane-Based Absorption Refrigeration System (ARS)" by Saeed Moghaddam
3. "Low Regeneration Temperature Adsorption Heat Pump in a Micro-Trigeneration System" by Reinhard Radermacher, Kyle Gluesenkamp, Suxin Qian
4. "High Efficiency Absorption Chiller-Heaters & Triple Effect Chillers" by Piyush V. Patel

2012 Summer Meeting in San Antonio:  
Seminar 15: Exploiting the Advances in Absorption Fundamentals for Transformative Impact
1. "Water/LiBr Absorption System Assisted Vapor Compression System for High Ambient Temperatures"
by Yunho Hwang
2. "Physical Properties of the Lithium Bromide + 1, 2-Propanediol Aqueous Solution" by Omar Abdelaziz
3. "High Efficiency Energy Recovery Utilizing Micro-Channel Heat & Mass Exchangers Absorption System"
by Ebrahim Al-Hajri

2011 Winter Meeting in Las Vegas:  
Seminar 46: Achieving Zero Energy Design with Absorption Cooling
1. "Design Considerations of a Solar-Fired Chiller System" by I. Mahderekal
2. "30-Ton Absorption Chiller Installation on Vacuum Solar Collector" by P. Patel
3. "Water-LiBr Enabling Technologies using Chemical Additives" by O. Abdelaziz



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 8.3 is Cognizant for the Following Standards:

ANSI/ASHRAE Standard 40: Methods of Testing for Rating Heat Operated Unitary Air-Conditioning and Heat-Pump Equipment
Status:  Latest approved = Standard 40-2014

ANSI/ASHRAE Standard 182: Method of Testing Absorption Water-Chilling and Water-Heating Packages 
Status:  Latest approved = Standard 182-2008 (RA 2013).  Currently under revision.

Other Activities

TIP: If MTG involvement add here otherwise leave blank.

Include other activities, such as MTG involvement, into this section.


ASHRAE Technical FAQs are provided as a service to ASHRAE members, users of ASHRAE publications, and the general public. While every effort has been made to ensure their accuracy and reliability, they are advisory and provided for informational purposes only, and in many cases represent only one person’s view. They are not intended and should not be relied on as an official statement of ASHRAE. Technical questions not addressed may be submitted to the ASHRAE Technical Services department at tse@ashrae.net.