Tech Update

AHRI’s TechUpdate e-newsletter is published three times a year and includes the latest information on AHRI’s research initiatives, including recently concluded research reports and ongoing projects.

The AHRI Research Program supports AHRI’s advocacy positions, standards program, and certification program. It is a pre-competitive, basic research program that provides AHRI members with the scientific knowledge and design tools needed for the development of the next generation of energy efficient, environmentally-friendly HVACR equipment.

The AHRI Research and Technology Committee administers the program. The Committee recommends and takes measures to promote research activities and provides guidance and direction to staff concerning research and technology programs of AHRI. AHRI research projects are funded and managed entirely by AHRI or one or more of its product sections. AHRI closely works with ASHRAE to leverage its program by co-funding with ASHRAE on projects that are of interest to AHRI members. Final reports are made available on AHRI’s website.

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December 2014


Click here to download a PDF version of the December 2014 TechUpdate.

AHRI Low-GWP AREP Phase II Testing

Phase II of AHRI’s Low-Global Warming Potential Alternative Refrigerants Evaluation Program (Low-GWP AREP) is well underway, with 15 new low-GWP refrigerant candidates selected for testing by 22 test entities from the United States, Europe, Asia, and South America, according to test companies’ interest. Twelve compressors will be tested in Phase II, in addition to 14 air conditioning products, e.g., air conditioners, heat pumps, rooftop units, and water chillers. Phase II also includes testing of five refrigeration products. Eight test plans include equipment performance testing under high ambient conditions.

AHRI will continue accepting test plans from interested parties provided they can complete tests and submit reports for review by April 10, 2015. Companies interested in conducting tests are encouraged to contact AHRI staff directly to request a copy of the Participants’ Handbook for test protocols, plan submission, and a list of available refrigerants.

This ongoing industry-wide cooperative research program is designed identify and evaluate promising alternative refrigerants for major product categories, including air conditioners, heat pumps and heat pump water heaters, chillers, ice makers, and refrigeration equipment. The program does not prioritize these alternatives; rather, it seeks to identify potential refrigerant replacements for high-GWP refrigerants, and present the performance of these replacements in a consistent and standard manner.


AHRI Projects to be Launched in 2015

AHRI plans to launch the following research projects in early 2015:

  • AHRI-8017: Study on Ignition Sources’ Energy
    The objective of the project is to evaluate energy produced by potential ignition sources in residential and commercial applications relative to minimum ignition energy of a list of A2L refrigerants, and investigate the likelihood of the ignition sources igniting the refrigerants.
  • AHRI-8018: Review of Refrigerant Recycling Programs
    The objective of this project is to conduct a literature survey and to interview key personnel to identify the types of refrigerant recycling programs implemented in different regions of the world, and to compare their effectiveness and success to those in the United States. Results of this research will provide guidance on estimating refrigerant emissions during the end-of-life recycling process.

AHRI Participates in 4th Symposium on Alternative Refrigerants for High Ambient Countries

Senior AHRI staff members presented papers at the 4th Regional Symposium on Alternative Refrigerants for High-Ambient Countries in Dubai on October 28-29. Focused on equipment and refrigerant use in places with high ambient temperatures, the conference was organized by the United Nations Environment Programme (UNEP), the Emirates Authority for Standards & Metrology (ESMA), the United Nations Industrial Development Organization (UNIDO), and ASHRAE’s Falcon Chapter.

AHRI’s papers focused on the region’s refrigerant transition. AHRI President and CEO Stephen Yurek addressed the need for hydrofluorocarbons (HFCs) to be included in the Montreal Protocol and emphasized that the Middle East region could expect to use HFCs for 10 years because it is still transitioning from hydrochlorofluorocarbons (HCFCs). AHRI Senior Vice President of Regulatory and International Policy Karim Amrane provided a report on Phase II of AHRI’s Low-Global Warming Potential Alternative Refrigerants Evaluation Program, which involves testing refrigerants at high temperatures. Presentations made at the symposium can be downloaded here.


NIST Hosts Workshop on the Exothermic Reaction of Halogenated Hydrocarbons

On October 27–28, the National Institute of Standards and Technology (NIST) hosted a workshop on the flammability of halogenated hydrocarbons, with an emphasis on safety considerations due to unwanted reaction. Two industries were represented: HVACR and water heating, with regard to the flammability of new low-global warming potential, ozone depletion potential refrigerants; and the fire suppression industry, with regard to clean-agent halon replacements. The workshop identified a list of research needs and priorities on the high-temperature reaction of halogenated hydrocarbons, and discussed the possible formation of an industry consortium.


AHRI Presents at Japan’s International Symposium on New Refrigerants and Environmental Technology 2014

The International Symposium on New Refrigerants and Environmental Technology was held in Japan, November 20-21, and provided a platform for international presentations, information exchange, and discussion on topics related to environmental technologies and low-global warming potential (GWP) refrigerants. AHRI staff provided an update on the status of Phase II of the Low-GWP Alternative Refrigerants Evaluation Program.

The symposium included presentations on extensive studies on safety and risk assessments of flammable refrigerants, listed below. Most of the work was organized by a research committee in Japan, established by the Japan Society of Refrigerating and Air Conditioning Engineers to exchange knowledge about safety issues and assess the risk of mildly flammable refrigerants in Japan.

  1. Hihara, E., Research project on risk assessment of mildly flammable refrigerants in Japan, JRAIA International Symposium, 2014
  2. HImamura, T., Sugawa, O., Experimental evaluation of physical hazards of A2L refrigerant assuming actual handling situation, JRAIA International Symposium, 2014
  3. Saburi, T., Wada, Y., Hazard assessment of the combustion of mildly flammable refrigerants, JRAIA International Symposium, 2014
  4. Higashi, T., Saitoh, S., Dang, C., Hihara, E., Diesel combustion of oil and refrigerant mixture during pump down of air conditioners, JRAIA International Symposium, 2014
  5. Taira, S., Watanabe, T., Takaichi, K., Overview of the risk assessment for mini-split air conditioners (RAC & Store PAC), JRAIA International Symposium, 2014
  6. Yajima, R., Overview of the risk assessment and safety guidelines for VRF systems using A2L refrigerants, JRAIA International Symposium, 2014
  7. Ueda, K., Chiller risk assessment and guideline by mildly flammable refrigerants, JRAIA International Symposium, 2014
  8. Papas, P., Zhang, S., Verma, P., Lord, R., Burns, L., Walter, W., Evaluations for 2L refrigerant flammability and ventilation mitigation requirements in machine rooms, JRAIA International Symposium, 2014

Department of Energy Building Technologies Office Develops R&D Roadmaps

The Department of Energy (DOE) Building Technologies Office (BTO) issued research and development (R&D) roadmaps on emerging HVAC technologies and next generation low-global warming potential (GWP) refrigerants. The BTO developed the roadmap on HVAC technologies to establish guidance on R&D activities to pursue that will aid in achieving its energy savings goals. For HVAC, BTO targets 12 percent and 24 percent primary energy savings by 2020 and 2030, respectively. The low-GWP refrigerants roadmap was developed to provide recommendations to BTO on R&D activities that will help accelerate the transition to low-GWP refrigerants across the entire HVACR and water heating industry.


Ongoing Research Projects Cover Wide Range of Products

AHRI’s research projects often take several months or even years to complete. The following projects are ongoing this year:

  • AHRI-8009: Risk Assessment of Refrigeration Systems Using A2L Flammable Refrigerants
    The objective of this project is to use fault tree analysis to conduct a risk assessment for small commercial refrigeration equipment using A2L flammable refrigerants. The scope of the risk assessment is to evaluate risks during the operation and service of HFC-32 (GWP of 675), HFO-1234yf (GWP of 4), or HFO-1234ze (GWP of 6) in a self-contained reach-in cooler and a single condensing unit connected to refrigeration unit(s).
    The project is ongoing at Gradient and is expected to be completed in February 2015. Currently, a draft final report is under review by the project monitoring subcommittee.
  • AHRI-8011: Field Evaluation for Combustion Appliance Auditing
    This project will identify currently recognized or commonly utilized procedures for evaluating the safety and performance of installed combustion equipment; will compare and contrast those procedures; and will provide information either to identify the correct procedure or to develop such a procedure if none of the existing ones is sufficiently correct.
    The project is ongoing at Gas Consultants, Inc., and is expected to be completed in June 2015.
  • AHRI-8012: Developing Fan Power Terminal Unit Performance Data and Models Compatible with EnergyPlus
    This project is to develop a broad range of fan/motor efficiency data that can be readily used in EnergyPlus. Models for alternative configurations/operations of series and parallel units will be developed. A leakage model is planned to be incorporated into the EnergyPlus model.
    The project is ongoing at Baylor University and is expected to be completed in December 2015.
  • AHRI-8013: A Study of Methods to Represent Compressor Performance Data Over an Operating Envelope Based on a Finite Set of Test Data
    This project has two objectives: (1) to determine the optimal method to represent performance data over the application envelop, which maximizes accuracy for a given number of test points; and (2) to estimate the level of uncertainty in each method as a function of measurement reproducibility and/or product-to-product variation, especially at the typical rating points given in the performance rating standard.
    The project is ongoing at Optimized Thermal Systems and is expected to be completed in April 2015.
  • AHRI-8014: The Effect of Lower Return Air Temperatures on Furnace Heat Exchangers
    Furnace installation manuals limit the return air temperature to 55° or 60°F, but many thermostats have the ability to regulate to as low as 40°F. Low-return air temperatures may compromise the life and robustness of heat exchangers. This project will establish the appropriate return air temperature to avoid unnecessarily stressing the heat exchanger. It will also establish guidelines for setback and extended absences set points to allow maximum energy savings while preserving heat exchanger integrity.
    The project is ongoing at Gas Consultants, Inc., and is expected to be completed in October 2015.
  • AHRI-8015: Leak Rates Assessment for Air Conditioning and Refrigeration Equipment
    This project will conduct survey-type research to analyze the information on the actual leakages for refrigeration equipment. The outcome will be a useful input to the equipment life cycle climate performance (LCCP) analysis and risk assessment for systems using mildly flammable refrigerants.
    The project is ongoing at ICF Incorporated LLC and is expected to be completed in March 2015.
  • AHRI-8016: Risk Assessment for Rooftop Units Using A2L Refrigerants
    The objective of this project is to use fault tree analysis to conduct a refrigerant ignition risk assessment for rooftop units using A2L flammable refrigerants. The scope of the risk assessment is to evaluate the refrigerant ignition risks during operation and service from using HFC-32 (GWP of 675) or HFO-1234yf (GWP of 4), or HFO-1234ze (GWP of 6) in rooftop units.
    The project is ongoing at Navigant Consulting, Inc., and expected to be completed in November 2015.

AHRI/ASHRAE Co-funded Projects Leverage AHRI Resources, Benefit Members

AHRI works closely with ASHRAE to leverage the AHRI research program by co-funding with ASHRAE on projects that are of AHRI members’ interest, some of which are listed below. All AHRI co-funded ASHRAE project final reports are available to AHRI members upon request.

Ongoing ASHRAE Projects:

  • AHRTI-ASHRAE-1467: Balancing the Latent Heat Load between Display Cases & Store Comfort Cooling
    This project seeks to provide a comprehensive assessment of energy savings potential in supermarkets by optimized design and operation of the combined HVACR systems.
  • AHRTI-ASHRAE-1507: Binary Refrigerant Flame Boundary
    The project aims to develop, through a literature search, a database of past pertinent binary flame boundary concentrations, and to determine, through laboratory measurements, values for 10 additional refrigerant component pairs of commonly used and newly introduced flammable/nonflammable refrigerants pairs. This project is ongoing at Safety Consulting Engineers.
  • AHRTI-ASHRAE-1535: A Heat Transfer and Friction Factor Correlation for Low Air-Side Reynolds Number Applications of Compact Heat Exchangers
    The objective of this research is to develop airside heat transfer and pressure drop correlations for high performance compact heat exchangers under low-air velocity conditions. The project is ongoing at Florida International University.
  • AHRTI-ASHRAE 1634: Guide for Sustainable Refrigerated Facilities and Refrigeration Systems
    The objective of the project is to develop a guide for sustainable refrigerated facilities and refrigeration systems. Information in the guide will be used for the design of new facilities, expansions, and remodels, as well as to provide guidance on improvements and operating methods that can also be applied to existing facilities. This project is ongoing at Massey University.
  • AHRTI-ASHRAE1641: Effect of Unsaturated Fluorocarbon Contaminants on the Reliability and Performance of HVACR Equipment
    This project aims to develop chemical reactivity information on unsaturated fluorocarbon contaminants to help the HVACR industry understand its impact on the performance and reliability of products. The results from this work will advance knowledge to support the industry in revising the limits for unsaturated compounds in various refrigerants (including new and reclaimed refrigerants) in operating equipment. This project is ongoing at Spauschus Associates.
  • AHRTI-ASHRAE1645: Development of New Accelerated Corrosion Tests for All-Aluminum Microchannel and Tube and Fin Heat Exchangers
    The objective of this research is to develop a new corrosion test, or justify the use of an existing standardized accelerated test, for both all-aluminum tube, and fin and brazed microchannel heat exchangers. This project is ongoing at University of Northern Texas.
  • AHRTI-ASHRAE 1665: R-40 Stability with HVACR System Materials
    This project seeks to determine the stability of R-40 (monochloromethane) with HVACR system materials, so that all industries that use refrigerants can determine the reliability and safety impacts of R-40 on equipment. R-40 has recently been determined to be the primary contaminant in mobile R-134a HVACR systems and, to a more limited extent, reported in R-22 and R-410A systems as well. This project is ongoing at McCampbell Analytical, Inc.