It’s hard to imagine a modern kitchen without a white cabinet humming in the background, keeping our food fresh. However, few people think that inside this household appliance circulates a substance that literally turned the refrigeration industry upside down and saved humanity from environmental disaster. For a long time, refrigerators operated on ammonia, sulfur dioxide and methyl chloride - extremely toxic and explosive substances.
That is why the appearance freon became a real technological breakthrough at the beginning of the 20th century. This is not just a gas, but the result of the painstaking work of chemists looking for the “ideal” refrigerant. The answer to the question of who invented the refrigerator with freon lies not in one name, but in the collaboration of practical engineers and chemical theorists.
In this article we will examine in detail the history of the creation of the first safe refrigerant R-12, learn about the role of the company General Motors and DuPont, and also find out how an accidental discovery in the laboratory led to the mass production of refrigerators available to everyone.
The dangerous era before freon: why a new gas was needed
Until the 1930s, home refrigerators were more of a dangerous experiment than a convenient household appliance. Substances that today seem absolutely unacceptable for everyday use were used as refrigerants. Ammonia had a pungent odor and was poisonous when leaked, sulfur dioxide caused suffocation, and methyl chloride was explosive.
Leaks occurred regularly, and this led to tragic consequences. Toxicity Old refrigerants were so high that one rupture of a pipeline in a city apartment could cause the death of an entire family or a fire in apartment building.
⚠️ Attention: In technology museums you can find old refrigerators from the early 20th century. It is strictly forbidden to try to connect them to the network or open the circuit, since residual ammonia or sulfur dioxide under pressure may remain in the system.
Engineers of that time understood: the refrigeration industry would reach a dead end if a safe alternative was not found. What was needed was a substance that was inert, nonflammable, odorless, colorless, and had suitable thermodynamic properties for contraction and expansion.
The search was conducted all over the world, but key developments took place in the United States. It was there that a request for the creation of synthetic gas was formed, which would make refrigerators a mass product, and not a luxury item for daredevils.
Thomas Midgley and Francis Lowe: the founding fathers of freon
The history of the creation of freon is inextricably linked with the name of the American chemical engineer Thomas Midgley Jr.. While working at GM General Motors (GM) Research Laboratory in Dayton, Ohio, he was tasked with finding replacements for hazardous refrigerants. Working with him on the project was Thomas Midgley Jr.'s chemist, Francis Lowe. Their work was carried out within a division that would later become known as Francis Low.
Their work was carried out within a division that would later become known as Kinetic Chemicals. Scientists didn't just search at random; they systematized the requirements for the new gas. The substance had to boil at a temperature just below zero, easily condense at room temperature and be absolutely safe for humans.
In 1928, Midgley conducted a famous demonstration that went down in the history of chemistry. He inhaled the vapors of the new gas and blew out a burning candle with them, proving the absence of toxicity and flammability. This gas became dichlorodifluoromethane, which received the commercial name Freon-12 (R-12).
The discovery of Midgley and Lowe made it possible to launch mass production. Chemical formula CCl2F2 turned out to be ideal for compressors of that time. This allowed the company Frigidaire (a subsidiary of GM) to begin producing safe refrigerators, which instantly changed the market for household appliances.
The role of DuPont and the launch of mass production
Although Midgley discovered the formula, its industrial implementation required enormous power. General Motors partnered with the chemical corporation DuPont, which took over the production of the new refrigerant on an industrial scale. The Freon trademark has become synonymous with all refrigerants, although initially it was the name of a specific product.
Production began in 1930. This event marked the end of the era of toxic gases in everyday life. Mass production allowed to reduce the cost of refrigerators, making them affordable for the middle class. Until this point, refrigeration units were the lot of the rich or were used only for commercial purposes.
| Parameter | Old refrigerants (before 1930) | Freon-12 (R-12) |
|---|---|---|
| Toxicity | High (deadly) | Almost zero |
| Flammability | High (explosive) | Non-flammable |
| Smell | Pungent, suffocating | Absent |
| Cost | High (due to risks) | Available |
The success of freon was stunning. Within a few decades, virtually all new refrigerators in the world switched to using chlorofluorocarbons (CFCs). This was considered the greatest achievement of the chemical industry of the 20th century.
Chemical properties and operating principle of R-12
What is so special about the substance invented by Midgley? Dichlorodifluoromethane has a unique combination of physical properties. It easily changes from a gaseous state to a liquid at moderate pressure, which was ideal for the piston-type compressors that dominated the technology of that time.
Unlike ammonia, freon does not dissolve in water and does not react with the metals from which the tubes and compressors were made. This significantly increased the service life of refrigerators. Previously, corrosion and chemical destruction of seals were a common cause of breakdowns.
The principle of operation remained classic: the compressor compresses the gas, turning it into a hot liquid, which gives off heat in the condenser (black grille at the back). Then, passing through the capillary tube and evaporator, freon expands sharply, taking heat from the fridge compartment.
⚠️ Attention: Despite its safety for humans when inhaled, freon is heavier than air. If there is a large leak in an unventilated area, it can displace oxygen, causing suffocation. Always provide ventilation during repairs.
For a long time it was believed that freon was an ideal substance. Its chemical stability, which delighted engineers in the 1930s, later became an environmental problem. CFC molecules are not destroyed in the lower layers of the atmosphere and can exist for decades, gradually rising into the stratosphere.
Ecological turn: from freon to new refrigerants
In the 1970s, scientists Sherwood Rowland i Mario Molina put forward the theory that chlorofluorocarbons (CFCs), which include classic freon, destroy the Earth's ozone layer. Under the influence of ultraviolet radiation in the upper layers of the atmosphere, chlorine is released from freon molecules, which catalyzes the breakdown of ozone.
This discovery led to the adoption of the Montreal Protocol in 1987. The document provided for a phased out of the production and use of ozone-depleting substances. A new era has begun in the refrigeration industry. Manufacturers were forced to look for a replacement for R-12.
Why was freon banned if it is safe for people?
Freon is safe for humans during household use (non-toxic, non-flammable), but is catastrophically dangerous for the planet on a global scale. One chlorine molecule can destroy thousands of ozone molecules. It was this long-term environmental effect that led to the ban.
It was replaced by hydrochlorofluorocarbons (HCFCs), such as R-22, which are less stable and break down faster, not having time to reach the stratosphere in large volumes. However, they were also found to be harmful. The modern standard is hydrofluorocarbons (HFCs), for example R-134a and R-600a (isobutane).
Interestingly, the modern isobutane (R-600a), which is now found in most new refrigerators, is essentially a return to hydrocarbons, but in microdoses and with an improved safety system. The circle is closed, but technology has stepped far forward.
How to determine the type of refrigerant in your refrigerator
If you are planning to repair or refill a refrigerator, it is critical to know what kind of gas was used in its creation. For older models this could be R-12, for newer ones (90s and 00s) it could be R-134a, and for modern ones it could be R-600a.
The information is usually contained on the technical sticker. It can be located inside the chamber, on the back wall of the case or on the base of the device. Look for the inscription “Refrigerant” or “Refrigerant.”
- 🧊 R-12 —used until the early 90s, prohibited, requires a complete replacement of the system during repairs.
- ❄️ R-134a —standard for household appliances from the 1990s to 2010s, requires synthetic oil.
- 🔥 R-600a —modern standard, flammable gas, requires special care when soldering.
Never try to fill the refrigerator with a gas that does not match the manufacturer's markings. Different refrigerants require different types of compressor oil and have different operating pressures. An error can lead to failure of the compressor or even an explosion.
☑️ Check before calling a technician
Frequently asked questions (FAQ)
Is it possible to replace freon in an old refrigerator yourself?
It is strictly not recommended. This requires special equipment (vacuum pump, pressure gauge station, scales), skills in soldering copper pipes and a license to work with refrigerants. In addition, old gases (R-12) are prohibited for use.
Is freon from a modern refrigerator harmful to health?
Modern refrigerants (R-134a, R-600a) in small quantities contained in a household refrigerator are not toxic to humans. However, with strong heating (fire), they can decompose with the formation of phosgene, a chemical warfare agent.
Why are there less freon in new refrigerators than in old ones?
Modern cooling systems have become more efficient, and heat exchangers are more compact. In addition, the use of isobutane (R-600a) allows you to achieve the same temperatures with a significantly smaller amount of substance (about 50-60 grams versus 150-200 grams for R-134a).
Who else besides Midgley was involved in the creation of the refrigerator?
We must not forget about Jacob Perkinswho created the first working prototype of a compressor in 1834, and Carla von Lindewho developed gas liquefaction technology. But it was Midgley who made the process safe for the masses.
What to do if the room smells of gas from the refrigerator?
Immediately open the windows for ventilation. Do not turn on electrical appliances or lights (to avoid sparks). Turn off the gas valve (if it is R-600a) or simply unplug the appliance if the smell is coming from the electronics and call a specialist.