Global Warming Potential: Is It Time for a Change?

What to expect with refrigerant phase-outs in HVAC


Chris Plummer, Product Manager, Gil-Bar Industries


If you’re a professional within the HVAC industry, you know that the EPA is constantly changing codes and regulations to be better to our planet. Sometimes, those changes can seem hard to understand or adapt to, but knowing the true impact of your equipment can help. Lately, the EPA has made changes to ensure equipment is not using “high global-warming-potential” (or GWP) refrigerants. Within the scientific community, there is a fear that the high GWP refrigerants can leak and in turn add to Ozone depletion.  As a result, we’ve seen certain refrigerants in the industry begin to “phase out.”

But what is Global Warming Potential and what are the other determining factors for a “sustainable” refrigerant? Well, it turns out there are three main criteria:

Global Warming Potential (GWP): The metric used to compare the global warming impact of greenhouse gases compared to a reference gas, Carbon Dioxide (CO2), where its GWP is equal to 1. For example, R-134a refrigerant has a GWP rating of 1,430, indicating that it has 1,430 times the 100-year warming potential of the same volume of CO2. R-410a has a rating of 2,088, indicating that it has 2,088 times the 100-year warming potential of the same volume of CO2. In this case, R-134a would be considered a more sustainable refrigerant.

Toxicity: Relative toxicity to humans, broken into two classes:

  • Class A (Lower Toxicity): Refrigerants for which toxicity has been identified at concentrations less than or equal to 400 parts per million (PPM).
  • Class B (Higher Toxicity): Refrigerants for which toxicity has been identified at concentrations greater than 400 parts per million (PPM).

Flammability: There are four classes of flammability (From Figaro):

  • Class 1: When tested, the refrigerant saw no flame propagation at 140°F (60°C)and 14.7 psia (101.3 kPa).
  • Class 2: When tested, the refrigerant exhibited flame propagation at 140°F (60°C)and 14.7 psia (101.3 kPa), had a heat of combustion less than 19,000 kJ/kg (8,174 British thermal units BTU/lb), and had a lower flammability limit (LFL) greater than 0.10 kg/m3.
  • Class 2L: When tested, the refrigerant had a maximum burning velocity of 3.9 in./s (10 cm/s)or lower when tested at 73.4°F (23.0°C) and 14.7 psia (101.3 kPa). The purpose of the 2L subclass is to reflect the lower flammability properties of the new low-GWP refrigerant options on the rise, such as hydrofluorolefins (HFOs), like R-1234ze.
  • Class 3: When tested, the refrigerant exhibited flame propagation at 140°F (60°C)and 14.7 psia (101.3 kPa) and either had a heat of combustion of 19,000 kJ/kg (8,174 BTU/lb) or greater or a LFL of 0.10 kg/m3 or lower.

Standards (like ASHRAE 15 and EN 378) and guidelines use this number to determine what size charge is permitted in an occupied space such that if one were to leak, it would not exceed the concentration limit.

So What Does It All Mean?

Over the past 30 years, some of the phase outs brought on by the EPA we have included: Ammonia, R-22, and R-123. The next refrigerants to be retired will be R-134a and R-410a. R-134a is commonly used in large tonnage HVAC equipment including Air-Cooled and Water-Cooled Chillers. R-410a is used in smaller HVAC equipment like Roof Top Units (RTUs), Variable Refrigerant Flow (VRF) units and even window units.

There are 12 states, including New York and New Jersey, that are seeing the phase out of R-134a by the end of 2023. The challenge we face now is that there is no replacement. R-134a had the best heat transfer properties and flammability rating compared to known legal refrigerants. As a result, the only options now will be to utilize a less efficient refrigerant or one with a higher flammability rating. A less efficient refrigerant will lead to more energy usage in order to get the same amount of cooling. Considering that most of our energy comes from fossil fuels, we will be adding more carbon to the atmosphere to obtain the additional energy required, having the opposite of the intended effect. Similarly, moving to Class 2 refrigerants introduce whole new challenges, having to take life safety into consideration. Moreover, most localities do not allow flammable refrigerants to be present in buildings, so we are at a crossroads.

Even for R-410a (Freon), we see the same challenges, with it being replaced by R-454b and R-32. Both of which are A2L refrigerants. Luckily, the R-410a phase-out will not happen until the start of 2025.

Almost all major manufacturers have decided already to go with an A2L refrigerant, compounding the effects previously outlined. While the end goal is to stay compliant and reduce global warming potential, we will need to see some local code changes to account for new equipment in the coming years.

Chris Plummer is a product manager at Gil-Bar Industries. Since 1986, Gil-Bar has been the HVAC solutions company that offers greater engineering expertise, with deeper commitment to client success, than any other firm.

Chris Plummer
(646) 584-5031

Getting Ready for the Heat: Before Your HVAC Acts Up

Avoid headaches with these tips from the pros

By Mike Furey, General Manager, MIH Systems Group

There is a famous saying within the HVAC industry: Components don’t die, something kills them. Component failure can lead to costly repairs, and when it happens, service technicians turn into de-facto detectives looking for the killer. Most of the time though, failures come from one thing: lack of maintenance.

Given the many levels of preventive maintenance required to keep equipment from dying, being proactive with all systems connected to your mechanical equipment is key. “Unnecessary breakdown” is a word no one likes to hear, but it’s caused when preventive action isn’t performed. During a formal maintenance visit, a trained technician inspects equipment looking for any possible defects in devices that could cause a failure, and when a dirty device or failed component is discovered, the technician can address the problem in real time, avoiding a breakdown.

So, what is the number one preventable cause of major damage and repair costs? Water Leaks. An unchecked leak can lead to a host of other issues, including clogged drain lines, slimy overflow in condensate drain pans, and more. While inspecting for leaks, it’s also a good idea to check for dirty air filters, worn fan belts, and dirty blower wheels.

Being proactive with your equipment doesn’t just prevent breakdowns either. It can improve normal operation as well, affecting:

  • Energy Efficiency: When equipment is maintained properly, it reduces stress on the internal machinery, allowing it to operate as designed.
  • Air Quality: Poor air quality is a direct result of an unclean air filter, but maintaining and replacing UV lighting and other devices that regulate the amount of air transfers performed throughout day are also just as critical.


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Just like for us, reduced stress extends life. This is especially important when talking about equipment that operates off electricity. When equipment consistently operates un-maintained, it uses more electricity, which causes overheating, additional stress, and equipment failure.

MIH Systems Group, of the Gil-Bar and Ambient HVAC collective, has advocated for peak efficiency, maintenance, and safety for each of its clients since its inception in 2009. MIH recommends regular maintenance checks every three months for commercial properties.


HVAC Critical Systems Checklist:

[ ] Inspect for Leaks

[ ] Check for Dirty Air Filters

[ ] How is your Fan Belt Looking?

[ ] Are your Blower Wheels Clean?


MIH Systems Group

20 West 36th Street, Suite 700

New York, NY 10018

(212) 714-0178

Geothermal Heat Pump Technology Approved As A Renewable Energy

Earth Month is a great time for commercial properties to take advantage of new and considerable tax benefits, while helping to reduce emissions from HVAC

By Chris Plummer, Product Manager, Gil-Bar 

For building owners, consulting engineers, and general contractors searching for new ways to enhance the efficiency and sustainability of cooling units while seeking to preserve the atmosphere and global ecosystem, the big news is geothermal heat pump technology.

The Inflation Reduction Act of 2022 introduced some exciting new opportunities for Owners and Developers in building sustainability. Under the new Act, geothermal heat pump technology is now classified as a “renewable energy,” offering considerable tax benefits and allowing you to keep BTUs in the building. The Federal Income Tax breaks offer:

  • 30% of Geothermal Heat Pump System costs
  • Direct rebates equal to the credit for non-taxable entities
  • No limit to the maximum credit or rebate
  • Exemption from AMT
  • Recognition for up to three years prior
  • Rights to sell and transfer
  • Use for more than one year

The Act also introduces the ability for commercial properties to take advantage of accelerated depreciation within their taxes, such as:

  • 5-Year MACR depreciation for Geothermal Heat Pump System costs
  • Bonus depreciation eligibility

In order to qualify for these enhanced benefits, you simply need to meet the following criteria:

  • The building is located within in the United States
  • Original use of the property begins with the taxpayer
  • Your construction commenced before 12/31/2034

In many cases, these benefits can result in a Return on Investment (ROI) in less than one year.

As industry leaders, Gil-Bar Industries has a variety of geothermal heat pump products that you can take advantage of today. From Geothermal Water Source Heat Pumps to Water Cooled Chillers, Gil-Bar has the solutions and expertise to help you take advantage of this recent change in legislation.

During the first week of March, Senior Account Executive at Gil-Bar, Nick Denson, organized a full week of presentations to customers in New York City with Dan Ellis, former President of ClimateMaster. These presentations went on to explain why the Inflation Reduction Act of 2022 is important to Building Owners, Developers and Consulting Engineers. “The excitement around this new law creates a win-win for everyone. Geothermal helps the environment and pays for itself in just a year.” says Denson. “The reactions to this news have been incredibly positive.” To schedule a presentation or talk to a Gil-Bar representative, call (212) 331-8272.