Many users of household appliances are wondering what the name of the refrigerator liquid is, which is directly responsible for cooling food. You can often hear the terms “freon”, “antifreeze” or simply “gas”, but the technically correct name for this substance is refrigerant. It is the circulation of this working fluid along the closed circuit of the system that allows heat to be removed from the internal chamber and transferred to the environment.
It is important to understand that in everyday life the word “liquid” often means a substance that under normal conditions can be in a gaseous state, but is compressed by a compressor and turns into a liquid at high temperatures. pressure. Refrigerant is a coolant that changes its state of aggregation during the cycle: by evaporating, it absorbs heat, and by condensing, it releases it. Knowing the exact name and type of substance used is critical when servicing or repairing the unit.
Modern industry uses several main types of such substances, each of which has its own chemical formulas and physical properties. If you are planning self-diagnosis or just want to understand the design of your refrigeration equipment, you need to clearly distinguish between the markings, since they are not always interchangeable. The wrong choice of refrigerant can lead to compressor failure or even cause a dangerous situation.
⚠️ Attention: Refrigerants are under pressure in the system. Independently opening pipelines without special equipment and a license is prohibited by the legislation of many countries and can be dangerous to health.
Freon: a general name or a specific substance?
The most common answer to the question of what the liquid in the refrigerator is called is the word “freon”. However, this is not entirely correct from a chemical point of view. Freon is a trademark that DuPont once used to designate its refrigerants. Over time, the name became a household word, just as any copier is called a “copier.”
In fact, this term hides a whole group of saturated aliphatic fluorinated hydrocarbons. Different models of refrigerators may use completely different chemical compounds, which are united only by the principle of operation. For example, in old Soviet models it was often used R12, which is now prohibited for production due to its destructive effect on the ozone layer.
Modern household refrigerators are most often refilled with ozone-safe analogues. The most popular today are R134a and R600a. They have excellent thermodynamic properties, but require different compressor lubrication oils and charging technologies. Therefore, if you hear that “freon has run out,” be sure to check what specific marking of the substance is required for your model.
The differences between the types of freons lie not only in the chemical formula, but also in the operating pressure in the system. Some types require more powerful compressors, others require more thorough evacuation of the circuit before filling. Replacing one type of refrigerant with another is possible only with a complete rework of the system, including changing the oil and often the compressor itself. This makes the issue of fluid identification a priority during repairs.
Main types refrigerants in household appliances
To better navigate the variety of working substances, it is worth considering the characteristics of the most common of them. Understanding their properties will help you correctly evaluate the recommendations of service centers and avoid unnecessary expenses.
- ❄️ R134a (Tetrafluoroethane): The most common refrigerant in refrigerators manufactured since the late 90s. It is non-toxic, non-flammable and has good refrigeration properties. However, it requires the use of synthetic POE oil, which is very hygroscopic (absorbs moisture).
- 🔥 R600a (Isobutane): A natural hydrocarbon refrigerant that is becoming standard in modern energy-efficient models. It has excellent cooling performance and is ozone-friendly. The main disadvantage is its high flammability, which requires special safety measures during installation.
- 🏭 R12 (Dichlorodifluoromethane): Used in technology until the 2000s. It was distinguished by high working pressure. Now banned by the Montreal Protocol, but still found in older operating units. When replacing, they often switch to R134a with an oil change.
The choice of a specific type of substance depends on the design of the heat exchangers and the power of the compressor. Engineers calculate the system so that it works as efficiently as possible with refrigerant. Using the wrong substance will cause the refrigerator to stop freezing or to overload.
Below is a comparative table of the main characteristics of popular refrigerants, which will help systematize knowledge:
| Parameter | R134a | R600a | R12 (obsolete) |
|---|---|---|---|
| Chemical basis | Hydrofluorocarbon | Hydrocarbon (isobutane) | Chlorofluorocarbon |
| Flammability | Non-flammable | Highly flammable | Non-flammable |
| Effect on ozone | Safe | Safe | Destroys |
| Oil type | POE (synthetic) | Mineral | Mineral |
⚠️ Attention: When working with R600a (isobutane) categorically It is forbidden to use an open flame or a sparking tool in the immediate vicinity of the leak, since the gas is heavier than air and accumulates below.
The principle of operation of liquid refrigerant
Many people mistakenly believe that “refrigerator liquid” simply pours into the chamber and cools everything around like ice in a bucket. In fact, the process is much more complex and is based on a physical phenomenon called phase transition. The refrigerant constantly circulates in a closed circuit, changing its state from liquid to gas and back.
It all starts in the compressor, which compresses the gaseous refrigerant, increasing its temperature and pressure. The hot gas then enters the condenser (the grill at the back of the refrigerator), where it cools and turns into liquid. It is at this moment that it releases heat into the room. Next, the liquid passes through the filter-drier and enters the capillary tube, where it expands sharply.
Why is the capillary tube so thin?
The capillary tube creates the necessary resistance to the flow of refrigerant, providing a pressure difference between the low-pressure and low-pressure sides of the system. Without this difference, evaporation will not be effective.
Once in the evaporator (inside the chamber), the pressure drops sharply and the liquid boils at a very low temperature, turning into gas. During this boiling process, it actively absorbs heat from the food. After this, the gas is sucked back into the compressor and the cycle repeats. This continuous process provides constant cold.
The efficiency of the entire system directly depends on the quantity and quality of the refrigerant. If there is a lack of substance in the system, boiling will begin too early, and gas will enter the compressor without having time to take off enough heat, which will lead to overheating of the motor. Excess liquid can cause water hammer, which will physically destroy the compressor valves.
How to find out what refrigerant is in your refrigerator
If you are faced with the need for refilling or repair, the first step should always be to identify the type of substance used. Manufacturers are required to provide this information to prevent errors during maintenance. You need to look for data on a special marking sticker.
Usually such a sticker is located inside the refrigerator compartment. Depending on the model, it can be found on the side wall, on the inside of the door or on the back wall of the food niche. Sometimes, in older models, technical information may be embossed on a metal plate on the back of the unit, but this is less common.
- 🔍 Search for markings: Look for a line with the word “Refrigerant”, “Refrigerant” or the abbreviation “R” followed by numbers (for example, R134a).
- ⚖️ Checking the weight: Next to the type of gas, its exact amount in grams is always indicated (for example, 130g). This is important for the technician when refueling.
- 📜 Technical passport: If the sticker is erased or missing, the exact information can be found in the operating instructions or on the manufacturer's website for the device model.
You should not rely on the color of the tubes or external signs. Although some refrigeration technicians have in the past painted freon cylinders in different colors for identification, there are no visual markers of the type of liquid in the refrigerator itself. The only reliable source is the documentation or the factory label.
Signs of a leak and the need for replacement
The refrigerant in a working refrigerator does not disappear anywhere. This is a closed system, and if there were no mechanical damage or manufacturing defects in welding the seams, then the cooling liquid should remain inside for decades. However, if you notice signs of a leak, you cannot ignore them.
The main symptom of a shortage working fluid is insufficient cooling. The compressor can work continuously without turning off, trying to gain temperature, but cold will not appear in the chambers. There may also be excessive heating of the motor-compressor or, conversely, its complete silence (if the thermal relay has tripped).
Visually, a leak can sometimes be determined by swelling of the inner or outer wall of the refrigerator (if the evaporator is built into the housing), the appearance of oily spots under the unit, or a characteristic hissing when the tube is damaged. In the case of R600a, leaks are often looked for using gas analyzers, since the gas has no odor.
⚠️ Attention: If you smell burnt wiring or see sparking in the compressor area, immediately unplug the refrigerator. This may be a consequence of the engine operating in a low-coolant mode.
Replacing refrigerant is not just “topping up”. The procedure requires a professional approach: finding the leak, eliminating it, evacuating the system to remove moisture and air, and only then refilling a precisely measured amount of the substance. Violation of the technology will lead to a rapid re-breakdown.
☑️ Symptoms of a refrigerant leak
Environmental aspects and the future of refrigerants
The refrigerant industry is constantly evolving, driven by environmental requirements. After it became known about the destructive effect of CFC and HCFC group freons on the ozone layer, the world community adopted a number of protocols limiting their use. This has led to the emergence of new generations of refrigerants. The current trend is towards the use of natural substances such as isobutane (R600a) or propane (R290), which have zero ozone depletion potential and minimal global warming potential. However, their flammability requires refrigerator manufacturers to increase the tightness of connections and use intrinsically safe electrics. refrigerants.
The current trend is towards the use of natural substances such as isobutane (R600a) or propane (R290), which have zero ozone depletion potential and minimal global warming potential. However, their flammability requires refrigerator manufacturers to increase the tightness of connections and use intrinsically safe electrics.
In the future, it is possible that even more effective and safe synthetic mixtures will appear that will reduce the energy consumption of household appliances to a minimum. But for now, R600a and R134a remain the uncontested market leaders, ensuring the safety of our products.
Users You can’t just throw the unit in a landfill, hoping that the gas will evaporate on its own. Specialized collection points ensure safe selection and neutralization of refrigerants, preventing them from entering the atmosphere.
FAQ: Frequently asked questions
Is it possible to fill a refrigerator with freon yourself at home?
Theoretically, this is possible if you have the equipment (vacuum pump, pressure gauge station, scales), but is highly not recommended. An error in the amount of gas or the presence of moisture in the system will lead to compressor failure. In addition, working with flammable gases (R600a) without experience is dangerous.
Why can’t you mix different types of refrigerants?
Different types of freons have different chemical structures and lubrication requirements. Mixing can lead to the formation of acids, which destroy the motor windings, or foaming of the oil, causing water hammer. Each type requires a clean system.
How often do you need to change the liquid in the refrigerator?
In a normally operating refrigerator, the refrigerant never changes. It circulates in a closed loop and is not consumed. Replacement is required only in case of repair after a leak or a manufacturing defect.
Is freon from a refrigerator dangerous for humans?
Modern freons (R134a, R600a) in small quantities contained in a household refrigerator are not toxic during short-term inhalation. However, R600a is explosive in high concentrations, and the combustion of any freons can produce toxic products (for example, phosgene), so they cannot be heated.
Can freon run out on its own?
No, the gas cannot “run out” or “evaporate” simply over time, since the system is sealed. If there is less freon, it means that a microcrack has formed in the weld or pipe through which the gas has escaped.