AC Applications

AC Applications



Current Refrigerant Solutions


R-22 Phase Out

The Montreal Protocol, a treaty initially signed in 1989 by most countries around the world aimed to reduce harm to the ozone layer. R-22, which was the predominant refrigerant for stationary air conditioning systems, a hydro-chloro-fluoro-carbon (HCFC), was targeted as one of these substances. HCFCs have been found to have a negative effect on the ozone layer and therefore, as part of the Montreal Protocol, are being phased out around the globe. In accordance with the Montreal Protocol, the US agreed to eliminate production of new equipment charged with R-22 and other HCFCs starting January 2010. A reduced or allocated amount of R-22 refrigerant will be produced to service the installed base equipment until 2020, at that time the production and distribution of virgin R-22 refrigerant will be discontinued. After extensive research R-410A, a hydro-flouro-carbon (HFC), was found to be the best R-22 replacement for stationary air conditioning applications for a number of reasons. Systems designed for R-410A were produced as early as the late 90’s and have since proven to be a reliable choice with positive impact on the ozone layer.

Read more on the Montreal Protocol and the R-22 Phase out.

This chart shows the amount of HCFC new production allowed by law over the time frame below the chart. The yellow line represents the phase down and cap for the US as noted above and the green line represents a similar phase down and cap for the EU.

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The Future of Refrigerants

Is R-410A Here To Stay?

Although HFCs such as R-410A are non-ozone depleting, they do fall into a category of substances including CO2, methane and others referred to as green house gases. These green house gases when emitted into the atmosphere are believed to trap in heat keeping the earth warm, ultimately contributing to climate change. See illustration below. R-410A along with the other HFC fluids, each have an assigned metric known as GWP (Global Warming Potential) based on their potential impact to global warming when directly emitted into the atmosphere. Many of these HFCs with high GWP values are coming under pressure globally to be phased down or eliminated. Various proposals around the world are being considered by governments and international treaties. One proposal referred to as NAP (North American Proposal) suggests a phase-down of HFC consumption by GWP be added as an amendment to the Montreal Protocol.

When considering a refrigerant’s impact on climate change, it is crucial to consider not only the direct effects of the refrigerant if emitted into the atmosphere, but also the indirect effects based on CO2 emissions that occur from producing the energy (electricity) required to power the air conditioning system. One metric used to estimate the net global warming impact of an air conditioning system with a particular refrigerant, is the TEWI metric, or Total Equivalent Warming Impact. As you can see from the illustration below, the indirect impact with typical air conditioning systems is a much bigger factor. Therefore, efficiency of the refrigerant is a very important factor when selecting any new alternative, especially when the primary interest is related to climate change.

The search for a refrigerant for air conditioning with (1) lower global warming potential and (2) equally efficient to R410A has proven to be very difficult. Emerson along with other key stakeholders in the industry are actively committed to evaluating various alternatives. In addition to considering lower GWP alternatives for air conditioning, it is also prudent we expedite the use of alternatives in applications where good alternatives have already been proven to be safe, efficient and relatively simple to implement. It is also important focus on containing leaks by improving design and maintenance practices in systems notorious for refrigerant leakage.


AHRI has recently announced that they will be completing a study for new low GWP refrigerants (AREP)  This is similar to the AREP study completed in the late 90’s which guided the industry to R410A as the best choice and alternative to HCFC R-22.

  • This study will identify and test potential alternatives for high GWP refrigerants 
  • Emerson Climate Technologies is actively participating in this study
  • Read more about AHRI’s study here

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Emerson Climate Leadership

Collaborating with Key Advocacy Groups – ACEEE

Next Generation Refrigerants: Standards and Climate Policy Implications of Engineering Constraints
Hung Pham, Emerson Climate Technologies
Harvey Sachs, American Council for an Energy Efficient Economy

There is no single perfect refrigerant for diverse air conditioning, refrigeration, and industrial applications. The predominant halocarbons (CFCs, HCFCs, and HFCs) combine excellent efficiency and safety with acceptable costs. However, they contribute to ozone depletion potential (ODP) and/or global warming potential (GWP). The Montreal Protocol has eliminated ODP by requiring replacement of CFCs and HCFCs with HFCs such as R-410A, R-407C, and R134a. The next focus is a worldwide technical and policy search for next-generation refrigerants with low global warming potential (LGWP). Potential options include “natural refrigerants such as carbon dioxide (CO2), hydrocarbons (HC), and ammonia (NH3) as well as HFOs and HFO/HFC blends. All involve significant trade-offs among GWP, energy efficiency, safety, and cost. Environmental policy must consider the indirect effects of increased CO2 emissions for less efficient refrigerants, not just the direct global warming (GWP) of the refrigerant.

Shaping Policy as Members of Key Associations – Alliance for Responsible Atmospheric Policy

The Alliance for Responsible Atmospheric Policy (ARAP) is an industry coalition that was organized in 1980 to address the issue of stratospheric ozone depletion. It is presently composed of about 100 manufacturers and businesses which rely on CFCs, HCFCs, and HFCs. Today, the Alliance is a leading industry voice that coordinates industry participation in the development of reasonable international and U.S. government policies regarding ozone protection and climate change.

Learn more about the Alliance.

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