Read more about the AIM Act in 2025 here.

Which states are affected by the AIM Act?

This rule would apply to the entire country, bringing alignment instead of state-by-state regulations. States can still issue their own, more stringent regulations. Some states, like California and New York, will still require attention.

Which refrigerants are affected?

This rule proposes to restrict the use of refrigerants by their global warming potential (GWP). Equipment using more than 200 lbs. of refrigerant will face a GWP limit of 150. Equipment using less than 200 lbs. of refrigerant will face a GWP limit of 300. Chiller systems will face a GWP limit of 700.

When will the AIM Act ruling be finalized?

Currently, the proposed rule is available for comments until January 30, 2023. The rule will be finalized in October 2023. We do not expect the GWP limits to change. However, the implementation date might get pushed back to help manufacturers and end users complete existing projects. Industry leaders are asking for clarification about how the implementation dates are defined. They also seek clarification on how “new projects” will be defined compared to retrofit or remodel projects.

Further Reading

Zero Zone has a new paper, “The National Plan for Refrigerant Regulations,” which has more information about the upcoming EPA regulations, which states will still have regulations to follow, and solutions that Zero Zone offers.

To know where we have come from, Zero Zone has a paper, “The State of Refrigerant Regulations,” which covers state regulations that affected the United States from 2019 through 2024.

The proposed rule and a succinct fact sheet are available on the EPA website: https://www.epa.gov/climate-hfcs-reduction/technology-transitions.

If you have questions about these regulations, please contact Zero Zone and ask to speak to our Director of Regulatory Compliance & Refrigeration Technology. If you want to learn about our offerings and plan for these regulations, contact our sales team.

NASRC Factsheet on Natural Refrigerants

The North American Sustainable Refrigeration Council (NASRC) recently published a factsheet outlining the impact of natural refrigerants on supermarket refrigeration. We aim to circulate this factsheet to ensure people do not miss this valuable resource and reminder of the benefits of natural refrigerants. The NASRC advocates for natural refrigerants. In their words, “Natural refrigerants are the climate-friendly solution to mitigate supermarket HFC emissions.”

Zero Zone Natural Refrigerant Systems

CO₂ Systems

We offer CO₂ subcritical and CO₂ transcritical systems. CO₂ systems can be indoors or outdoors, set up inside custom electrical mechanical centers (CEMCs), built as full racks or condensing units, and be part of booster systems and cascade systems. This versatility unlocks CO₂ as a viable solution for warm and cool climates for all sorts of customers, and Zero Zone has been shipping these systems across the United States with great results.

Ammonia Systems

Ammonia is a great choice for industrial customers and ice arenas. Low-charge ammonia systems can be utilized indoors, outdoors, and in CEMCs. We have many years of experience and knowledge in ammonia, and we are ready for your project.

EPA Regulations and Assistance

With increasing EPA regulation limiting the continued use of HFC refrigerants, Zero Zone is eager to assist you with deciding which natural refrigerant system would be best adapted to your specific application. Begin a conversation with us. Contact your local Zero Zone sales rep today.

What is the best refrigerant for my system? As government regulations push the industry away from high global warming potential (GWP) refrigerants towards low GWP options, now is the right time for natural refrigerants. Zero Zone natural refrigerant systems provide the solutions you need to meet your objectives and government regulations. A couple recent projects include a CO2 transcritical system for Rufus Brubaker Refrigeration and an ammonia chiller for Air Management Technologies.

System Facts: 200-Ton CO2 Transcritical System

• Customer: Rufus Brubaker Refrigeration
• State: Pennsylvania
• Application: Process refrigeration
• System Type: Parallel system located indoors
• Capacity: 150 tons used for medium temp, 50 tons used for low temp
• Features: Parallel compression, adiabatic gas cooler, hot gas defrost
• Energy Savings: Heat reclaim for facility water

CO2 refrigerant (R-744) grows increasingly important to the refrigeration industry as a natural replacement for high GWP refrigerants. Improvements to CO2 transcritical technology make CO2 feasible and reliable in more regions, including Pennsylvania where this new system is located. CO2 compressor discharge offers high-quality heat that can be repurposed through a heat reclaim system. Rufus Brubaker’s customer uses that reclaimed heat for their facility’s warm water.

John Collins, Industrial Sales Manager – East for Zero Zone, commented that “Rufus Brubaker is a longtime customer of Zero Zone. When they made the decision to pursue CO2 refrigeration for their customer, they came to Zero Zone as a trusted partner to deliver a successful project. Our team worked closely with Rufus Brubaker all the way through design concept, fabrication, installation, and start-up to assure a smooth project delivery and satisfied end user.”

System Facts: 150-Ton Ammonia Chiller

• Customer: Air Management Technologies
• State: Illinois
• Application: Process chilling
• System Type: Outdoor parallel system (OPS) configuration
• Capacity: 150 tons used for process cooling
• Features: Screw compressors, adiabatic condenser, low-charge plate chiller heat exchanger
• Energy Savings: VFD compressor control and DC motor condenser control

A large food processing organization globally recognized for their environmental and sustainable processes chose to install a low-charge ammonia (R-717) chiller manufactured by Zero Zone as part of a worldwide R-22 equipment phase-out. The low-charge ammonia chiller was selected to meet health and safety standards for both their employees and the surrounding neighborhood community. The package chiller was customized to provide the same low temperature glycol refrigeration capabilities of chemical refrigerant chillers while exceeding target GWP objectives. John Collins chimed in that choosing ammonia “is a future proof and environmentally friendly solution.”

Making an Educated Decision

There are many practical reasons to still consider HFCs. Traditionally, HFCs are seen as a low cost and familiar option. However, it is sometimes difficult to know where HFCs can be used because high GWP refrigerants are being increasingly regulated by individual states. To get started on understanding HFC restrictions, read our news article and white paper about state refrigerant regulations.

Likewise, there are many practical reasons for using natural refrigerants. CO2 is one of the safest refrigerants to use. Ammonia systems are some of the most efficient and have been used safely in industrial applications for many decades. Both CO2 refrigerant and ammonia refrigerant are readily available. Of course, the biggest benefit to natural refrigerants is that they are environmentally sound and meet global sustainability goals.

So, if either synthetic refrigerants or natural refrigerants can be reasonable choices, how do you know which to pick? A good place to begin is by contacting your local Zero Zone sales representative and starting a conversation. They will help you select the best refrigerant for your needs, whether it is synthetic or natural. Fill out a contact form or give us a call (cases 800-247-4496; systems 800-708-3735). We would love to talk refrigerants with you.

The Crown Coliseum in Cumberland County, NC, is home to the Fayetteville Marksmen minor league hockey team. It also became the home to a brand new Zero Zone ColdLoop™ Ice Arena Chiller.

After years with an old R-22 system, Cumberland County turned to Zero Zone for a new chiller using ammonia. Ammonia is an industrial-grade refrigerant. “Ammonia as a refrigerant is an excellent choice,” Industrial Sales Manager John Collins explained. “It is perfectly suited for a low-temperature chiller application: highly efficient and very reliable.” Ammonia is a future-proof refrigerant with no ozone depletion potential (ODP = 0), no global warming potential (GWP = 0), and high performance. It is one of the most prominent natural refrigerants, which is appealing as an environmentally responsible option.

Cumberland County also chose many excellent cost-saving features: highly efficient screw compressors, evaporative condenser, PLC control system, variable frequency drives (VFDs), and, most notably, a heat reclaim system. Their heat reclaim system repurposes compressor discharge heat to warm the subfloor under the ice, ensuring that the subfloor will not freeze or crack. Heat reclaim systems repurpose the waste heat that otherwise would be released at the condenser without benefitting the arena.

Most importantly, the chiller produces high-quality ice for the hockey team. The Fayetteville Marksmen skate confidently because their home ice is formed by a ColdLoop™ Chiller.

We take our home refrigerators for granted. We put food into the refrigerator, and it makes the food cold. But actually, the refrigerator is not making the food cold; it is removing heat from the food. That might sound counterintuitive, so we invite you to open the door to the world of refrigeration by learning about the basics of the refrigeration cycle.

Heat Transfer & Pressure

Before we discuss the refrigeration cycle, we must briefly discuss heat transfer. Heat always transfers from warm to cold. You can see evidence of this in your beverage of choice. Your morning coffee may start hot, but as the day wears on, it gets cooler because heat transfers into the surrounding air. At lunch, your soda warms up as heat transfers from the surrounding air. This is called sensible heat transfer. You can remember this by thinking about how you can sense (feel) the change. The coffee mug feels hot as heat transfers to you; the soda can feels cold as heat transfers from you.

Heat transfer can also cause a substance to change state between solid, liquid, and gas. This is called latent heat transfer. For example, H₂O can exist as a solid (ice), a liquid (water), or a gas (steam). At sea level, H₂O will be water between 212°F (100°C) and 32°F (0°C). If water is heated beyond 212°F, it will evaporate into steam. If water is cooled below 32°F, it will freeze into ice. As a substance changes state, its original state will be reduced as the other state increases. For example, as ice melts, it disappears and the amount of water increases. If enough heat transfers, the substance will cease to exist in its original state. Latent heat transfer (changing state) takes more heat than sensible heat transfer (changing temperature).

Another factor is how pressure relates to temperature. Boiling points vary depending on the pressure surrounding the substance. At sea level, water boils at 212°F, but if you travel to Denver or Pikes Peak in Colorado, the atmospheric pressure is lower and the boiling point will be lower.

The Refrigeration Cycle

Your unfinished can of soda is now warm. How do you chill it again? You may think the answer is to add cold to it, but remember that heat only moves from warm to cold. It is more accurate to say that you are actually removing the heat from the soda by transferring that heat to another, colder object. This is the concept behind the refrigeration cycle.

The refrigeration cycle comes from the work of William John Macquorn Rankine, who discovered how to transfer heat away from objects that were already cool. Historically, this could be done by placing objects into an ice box. Ice works well as a refrigerant because it maintains a constant 32°F temperature. Warm product (milk, meat, etc.) transfers heat to the ice (latent heat transfer), causing the ice to melt into water. The water (full of heat) drains away, and the refrigerated space and product remain cool.

All modern refrigeration systems have four main components that work together to move heat: the evaporator, the compressor, the condenser, and the expansion device. Imagine that heat moves in a “bucket” and follow the bullet points which correspond to the figure.

1. The evaporator gathers/absorbs heat from the refrigerated space into a “bucket.” The “bucket” is low-pressure, and it changes state (latent heat transfer) as it absorbs heat. Then the evaporator moves the low-pressure, heat-filled “bucket” to the compressor.
2. The compressor applies pressure, which compresses the heat-filled “bucket.” The heat-filled “bucket” changes from low-pressure to high-pressure as the compressor pushes it from the colder evaporator to the warmer condenser. When pressure is added, the temperature of the “bucket” also increases.
3. The condenser takes the high-pressure, heat-filled “bucket” and releases the heat from the “bucket” to the outside air (or other application). The “bucket” changes state (latent heat transfer) again as it releases heat.
4. The expansion device relieves the pressure on the empty “bucket.” When pressure is reduced, the temperature also decreases. The “bucket” cools and expands on its way to the evaporator to absorb more heat again.

The downside of using ice as the “bucket” is that more ice must constantly be added as it melts away. Modern refrigeration systems needed a long-term solution. Refrigerants are the modern “bucket” because refrigerants can continually absorb and release energy without escaping the system. Refrigerants change state between a liquid to a gas. Refrigerants must be able to boil at low pressures and low temperatures to be efficient.

High-glide refrigerants have a unique effect on a refrigeration system.

Have questions? Contact us and ask for our Director of Regulatory Compliance & Refrigeration Technology.

The California Air Resources Board (CARB) has officially published details about the California Cooling Act, which will take effect on January 1, 2019. The Act, which is based on vacated EPA SNAP Rule 20, prohibits HFC refrigerants with high global warming potential (GWP)—such as R-404A and R-507A—for supermarket systems, condensing units, and self-contained units.

The California Cooling Act affects new and retrofit equipment. Manufacturers cannot sell equipment using prohibited refrigerants that are manufactured after January 1, 2019.

CARB Definition for New Refrigeration Equipment:

1. Any refrigeration equipment that is first installed using new or used components; or
2. Any refrigeration equipment that is modified such that it is:
   1. Expanded after the date at which this subarticle becomes effective, to handle an expanded cooling load by the addition of components in which the capacity of the system is increased, including refrigerant lines, evaporators, compressors, condensers, and other components; or
   2. Replaced or cumulatively replaced after the date at which this subarticle becomes effective, such that the capital cost of replacing or cumulatively replacing components exceeds 50 percent of the capital cost of replacing the entire refrigeration system.

If the retailer or engineer is unsure whether the work will classify as a new system, they should contact the Refrigerant Management Program Hotline at 916-324-2517 or rmp@arb.ca.gov.

Additional Reading:

Refer to the following for more information about California’s regulations or the EPA regulations that affect the rest of the country:

• CARB Bulletin about California Regulations: https://content.govdelivery.com/accounts/CARB/bulletins/21f36dd
• Zero Zone Guide to Recent EPA Regulations: /epa-regulations-retailers-responsibilities/

For further information, contact Zero Zone at 800-247-4496 and ask for our Department of Regulatory Compliance and Refrigeration Technology. This message is informational only, and customers should review the new regulations fully to ensure compliance.