Freon: an aerosol propellant, refrigerant, or organic solvent consisting of one or more of a group of chlorofluorocarbons and related compounds. – Dictionary.com
Freon is a trademark of the Du Pont Corporation, but the term freon has come to represent any generic formulation of liquid refrigerant. Until 2010, air conditioning systems relied on R-12 or HFC-134a, with the latter being introduced to reduce the environmental damage caused by the former. Currently, air conditioners are built with a liquid refrigerant called Puron that allows your AC system to minimize atmospheric damage and run more efficiently.
Regardless of its formulation, a liquid refrigerant is what makes your air conditioner able to behave like an air conditioner. The refrigerant is circulated as a liquid through the system under high pressures. It absorbs heat from the air, retains that heat until it is moved away from the heat exchanger, and then disperses it as the high temperature turns into a gas. It’s a complicated chemical process that is far beyond the understanding of your friendly HVAC content writer, so today, we’re both going to learn a little something about Houston’s most important home appliance, our hero, the air conditioner.
Several types of liquid refrigerants have been used in the relatively brief lifetime of air conditioning, but Freon was the original game changer.
Was Freon the First Liquid Refrigerant?
Early residential and commercial refrigerators were limited to ammonia or methyl chloride as liquid refrigerants. Both chemicals were effective at drawing heat from the air and capable of small chilling tasks, like keeping food cold inside an enclosed space. What the early refrigerators did equally well was leak liquid refrigerant from their primitive internal pipe coils.
The problem with the chemical coolants was their volatility, with ammonia leaks producing respiratory issues and eye irritation. Methyl chloride was easily the more dangerous of the two during these common leaks, as it could leave chemical burns with only a minimal amount of exposure.
General Motors Gets on the Road to Freon!
Beginning in the 1920s, automotive manufacturer General Motors formed a research team in conjunction with the Du Pont Corp. to replace those dangerous refrigerants that were then in use. The team improved on existing formulations of fluorocarbons, which are by-products of methane, ethane, and propane, to create a non-toxic liquid refrigerant. GM partnered with the DuPont Chemical Company in 1930 to introduce the first formulation of Refrigerant-12, or Freon as it’s known commercially.
Freon –in its original R-12 and updated R-22 formulation for the next fifty years—was used in all refrigerators and every residential, commercial, and automotive air conditioner. As a non-toxic gas, little concern was given to the incidental release of Freon into the air from AC system leaks or from consumers attempting to charge the AC in their 1971 Gremlin.
A strange thing was happening while Freon was working hard to cool the inside of our homes; what was outside of our homes was getting hotter every year.
Freon Was Great Until It Wasn’t.
By the late 1960s, environmental concerns about smog, water pollution, and the overall quality of the planet’s air came to the forefront. Scientists became aware in the early 1970s that the protective layer of ozone that reduces the intensity of the sun’s ultra-violet rays was disappearing. Initially thought to be the result of contrails from supersonic aircraft and the Space Shuttle (as both vehicles flew high enough to pollute the stratosphere), it was found that chlorofluorocarbons were to blame.
When it was discovered late in the twentieth century that liquid refrigerants were harmful to the environment, a move began to phase them out. Reaching its zenith in the mid-1960s, the links between Freon, the rapidly depleting ozone layer, and rising global temperatures were first uncovered. Even with evidence of the dangers laid out, it took until 1978 for the US Government to enact the first ban on CFCs.
Initially, this ban was limited to aerosol spray cans that spit out products like AquaNet and Cheez-Whiz, but its use in air conditioners would continue for another two decades. In the meantime, work on alternatives to CFC refrigerants continued as international committees were formed to investigate and promote the immediate and long-term dangers to the environment.
What Was the Alternative to CFCs?
By 1986, the DuPont Corporation had patents in hand for a new refrigerant product, hydrochlorofluorocarbons (HCFCs), that were water-based (hence the “hydro”), and therefore would break down before reaching the ozone layer. HCFC-134a became the “New Freon” in the same year “New Coke” came and went, but its impact would linger much longer than six weeks.
The best feature of the new HCFCs was that the homeowner didn’t have to replace their entire HVAC system to use them. Changing from R-12 to HCFC-134a was as simple as having a local HVAC company evacuate the old refrigerant and replace it with HCFC-134a. Many well-meaning do-it-yourselfers’ attempted to change out their own Freon, neglecting the “evacuation” step, resulting in leaks from over-pressurization in the cooling lines. Combining the two refrigerants was illegal and dangerous, as the two liquids require different operating pressures and temperatures. Far too many AC compressors needlessly lost their lives during the mistakes made during “Great Freon Change Over.”
As the end of the twentieth century approached, Freon was still battling the ozone layer, but its reduction in use helped the ozone layer regenerate in some spots above Australia. But, its replacement HCFC-134a quickly created an environmental concern of its own, as it generated chlorine molecules in the stratosphere. The HVAC industry couldn’t catch a break and once again needed another variation of liquid refrigerant. By eliminating the chlorine component from Freon, the Honeywell Corporation created Puron, and the refrigerant class of hydrofluorocarbons (HFCs) was born.
Just seven years shy of celebrating its 100th birthday, in 2015, air conditioner manufacturers stopped producing units that use Freon. In January 2020, all worldwide production of Freon came to an end.
What is Puron?
Puron belongs to a new class of liquid refrigerants, the HFCs, which are far more efficient than any previous formulation, allowing for more precise compressor motor control. AC units running on Puron are equipped with variable speed compressor fans to keep your system from overworking on low-demand days and help them compete with the hottest Houston afternoon. Systems that operate on Puron are far more efficient, perform better, and have a longer mechanical lifespan than any Freon-based air conditioner.
Does the Freon Phase-Out Mean I Need to Replace My AC?
You aren’t going to need to replace your Freon-based air conditioner, as long as it’s working correctly. Even though Freon is no longer being manufactured or imported, a limited amount will be available for at least the next couple of years. Make sure your Freon-based AC system is maintained correctly, isn’t overworked on scorching days, and have it pressure tested for refrigerant leaks at least once a year.
Why are Refrigerants Harmful to the Environment?
The problem with CFCs and HCFCs is the hydrocarbons that they contain, a combination of fluorine, carbon, and chlorine atoms derived from methane. When these compounds are released into the air, they work against the ozone layer in the upper atmosphere. The ozone layer makes life on the planet possible by shielding the earth from ultraviolet rays from the sun. Without the protection from UV-B rays, the threat of skin cancer increases, as does the planet’s overall temperature.
The good news is that we could figure this issue out before CFCs could cause the entire ozone layer to be destroyed. The bad news is that after decades of reliance on Freon, the push was on to develop a non-environmentally destructive refrigerant that would be as effective.
And as affordable.
How Do I Determine What Refrigerant I Need?
If your air conditioner was made before 2010, your unit probably uses Freon. The bad news for these aging units is that no new Freon is being made for them, rendering them obsolete should they develop a refrigerant leak. The supply of already existing R-22 Freon is dwindling rapidly, so replacing an air conditioner that still runs on Freon is a timely decision.
Any air conditioner made after 2010 requires the newer liquid refrigerant branded as Puron or R-410A. Puron is different from Freon as it is not a CFC, does not deplete ozone, and absorbs and disperses heat.
Can I Change My Current Freon Based AC to Use Puron?
No. To do the similar job of Freon, Puron requires much greater in-line pressures that older compressors and refrigerant lines couldn’t survive. Making the switch from Freon to Puron will require purchasing a system that runs on R-410A, which may qualify you for some tax credits for making the change.
Check with your tax advisor if you install a new AC system.
What Are the Benefits of Puron vs. Freon?
Reduced Environmental Damage: Although Puron is still a chemical compound like Freon, Puron isn’t nearly as damaging to the environment. It has an ODP (ozone depletion potential) of zero, meaning it poses no threat to the ozone layer.
Reduced Cost: As R-22 continues to be phased out, it will become harder and harder to find, driving up cost. If your local HVAC company doesn’t have a source for Freon, they’re not going to be able to service your system, requiring you to locate a Freon-friendly HVAC company.
Better Performance: Freon doesn’t disperse heat nearly as well as Puron does, which is often why compressors burn out in older AC units. The compressor won’t have to work nearly as hard, as Puron’s ability to change state according to temperature will aid in cooling your entire home quickly.
Air conditioners that still run on Freon are getting older, and HVAC equipment doesn’t age like wine. The older an AC system is, the less efficient it is going to be. Moving parts and their related bearings wear out, making systems run hotter –and louder—than they did when new.
If it’s time to think about installing a new air conditioning system, give Nick’s Plumbing & Air Conditioning a call today. Our experts can perform an in-home assessment of your current system and inform you of the benefits of switching to a Puron AC system.