When the refrigerator stops freezing and the compressor runs continuously, the owner’s first thought is often “gas has come out.” In everyday life, this gas is called freon, although technically this is the name of a specific chemical compound that has become a common noun for all refrigerants. Freon acts as a coolant that circulates in a closed circuit, taking heat from the chambers and releasing it into the environment through a radiator on the rear wall.
Many people mistakenly believe that the leak of this substance is accompanied by a pungent odor or visible fog, as in films. In fact, modern refrigerants are colorless and odorless, and their leakage often occurs in microscopic portions through microcracks in the metal. Understanding the physics of the process will help you quickly diagnose a malfunction and not become a victim of unscrupulous craftsmen who can “fill” the system with air for the sake of profit.
In this article we will look in detail at what gases are used in modern models Indesit, Atlant or Bosch, how they differ from those that were used twenty years ago, and what to do if you suspect a violation of the tightness of the circuit. Modern freons (R600a, R134a) are safe for the ozone layer, but R600a is explosive at a concentration above 6% in the air.
What is freon and how does it work in the cooling system
Freon, or refrigerant, is a volatile substance with a low boiling point that easily passes from liquid to gaseous and back. It is this cycle of phase transitions that allows the refrigerator to create cold. The compressor compresses the gaseous freon, heating it, after which the hot gas enters the condenser (grid at the back), where it cools and turns into liquid.
Next, the liquid refrigerant passes through the capillary tube and enters the evaporator inside the chambers. There, the pressure drops sharply, the liquid boils at a very low temperature, actively absorbing heat from the products. After this, the gas is sucked back into the compressor and the cycle repeats. This process provides the stable temperature necessary for storing food.
It is important to understand that freon is not consumed during operation, like fuel in a car. The system is sealed, and if the equipment is in good condition, the amount of gas remains unchanged for years. If the refrigerator has stopped cooling, it means that the tightness of the circuit is broken or the compressor has failed, and not “the gas has run out.”
- 🧊 Evaporation occurs inside the chambers, taking away heat.
- 🔥 Condensation occurs outside, giving off heat to the room.
- ⚙️ Compression creates the pressure necessary for circulation.
Main types of refrigerants: R134a, R600a and R12
Over the decades of the evolution of refrigeration technology humanity has changed several generations of refrigerants. Old Soviet and post-Soviet models often ran on R12 (difluorodichloromethane). This substance did an excellent job of cooling, but was considered harmful to the Earth's ozone layer, so its production and use in new technology is prohibited by international protocols.
It was replaced by R134a (tetrafluoroethane). It does not deplete the ozone layer, but has higher system pressure and requires synthetic oil to lubricate the compressor. This gas is still widely used in many models in the mid-price segment. It is inert and non-flammable, which makes it relatively safe for household use.
The modern standard for energy efficiency is R600a (isobutane). This is a hydrocarbon gas that has excellent refrigeration properties and makes compressors quieter and more economical. However, it has a serious drawback: it is explosive. That is why the repair of refrigerators using isobutane requires special qualifications and special equipment.
| Type of freon | Chemical formula | Safety | Where used |
|---|---|---|---|
| R12 | CCl2F2 | Harmful to ecology | Old models before 2000 |
| R134a | CH2FCF3 | Safe, does not burn | Modern classics |
| R600a | C4H10 | Explosive | New energy efficient |
⚠️ Attention: If you hear a hissing sound when the tubes of a refrigerator with R600a gas are damaged, immediately leave the room and ventilate it. A spark from the light switch can cause a bang.
Signs of a freon leak and fault diagnosis
How to understand that there is no gas in the system? The most striking symptom is the compressor running without stopping. You can hear the smooth hum of the motor, but the cold does not appear in the chambers. The thermostat “thinks” that the temperature is not low enough and does not give a command to turn off, trying to compensate for the lack of refrigerant by endless operation.
The second sign is the lack of heating of the condenser grille on the rear wall. During normal operation, the grate should be warm or even hot (depending on the mode). If the motor is humming and the grille is cold, it means there is no freon in the system or there is critically little of it to create pressure. Swelling of the side walls of the refrigerator may also be observed if the evaporator is built into the body.
Sometimes a leak can be detected visually or audibly if the damage is significant. Oily spots may appear in areas of microcracks, as freon circulates along with the oil. However, you should not rely on this: often leaks occur in the foamed part of the housing or in hard-to-reach places where oil is immediately absorbed into the thermal insulation.
☑️ Leak diagnostics
There is a myth that freon has an odor. This is wrong. If you smell a burning or chemical odor, this may indicate overheating of the wiring, melted insulation, or decomposition of oil in the compressor, but not the release of the refrigerant itself. Diagnostics should be carried out by a professional leak detector or the method of soaping the connections, and not rely on the sense of smell.
Is it possible to fill a refrigerator with freon with your own hands
Theoretically, the filling process looks simple: you need to bleed off the remaining gas, evacuate the system, solder in a new valve and pump in the required amount of refrigerant. In practice, refilling the refrigerator doing it yourself is a lottery with a high risk of permanently destroying the equipment. The main problem is not in the gas itself, but in preparing the system.
Before refilling, vacuuming is required. If air or moisture remains in the system, acid is formed during compressor operation, which corrodes the motor windings from the inside, and the system becomes clogged with ice plugs. Without a professional vacuum pump and pressure gauge station, it is impossible to perform this stage efficiently.
Why can’t you just “add” gas?
Adding freon without vacuuming the system is a mistake. Various gases and oil may react, and air remaining in the system will cause the capillary tube to become clogged with ice. The refrigerator will work for an hour, and then the compressor will burn out or the system will clog.
In addition, each type of refrigerant requires its own oil and a strictly dosed amount of the substance. Overfilling or underfilling will lead to incorrect operation. For R600a, an error of 10-15 grams can be critical. Therefore, if you do not have experience working with refrigeration equipment, it is better to call a specialist.
- 🛠️ Special tools are required: station, pump, scales.
- 🔥 Risk of fire when working with isobutane (R600a).
- 💰 The cost of a technician’s work is often lower than the price of purchasing equipment for a one-time refill.
Table of pressure and boiling point of refrigerants
For specialists, an important parameter is the boiling pressure at different temperatures. This data allows you to understand whether the system is working correctly. In domestic conditions, these numbers are not necessary to know, but they show how different gases require different approaches to maintenance.
For example, R134a at a temperature of -25°C has a pressure of about 0.68 bar, while R600a at the same temperature shows negative pressure (vacuum). This means that if R600a leaks, air is guaranteed to be sucked into the system unless artificial pressure is created, which once again emphasizes the difficulty of repair.
| Refrigerant | Boiling point (1 atm) | Pressure at +25°C | Oil type |
|---|---|---|---|
| R12 | -29.8°C | 6.5 bar | Mineral |
| R134a | -26.1°C | 6.6 bar | Synthetic (POE) |
| R600a | -11.7°C | 3.6 bar | Mineral/Alkylbenzene |
⚠️ Attention: Specifications (pressure, oil type) may vary depending on the specific compressor model and environmental conditions. Always check the technical documentation on the nameplate of your device before starting work.
Preventing leaks and extending service life
In order not to encounter the problem of freon leakage, it is important to operate the refrigerator correctly. The main reason for the appearance of microcracks is corrosion. It often occurs due to the fact that the floor at the installation site is constantly wet, or the back wall is pressed close to the wall, disrupting ventilation and causing condensation.
Never pick at the ice in the freezer with sharp objects. Damage to the evaporator means a guaranteed and immediate leakage of the entire volume of gas. If you defrost the refrigerator manually, use only soft rags and warm water, but not a knife or screwdriver.
It is also worth protecting equipment from mechanical shocks when moving. Sharp bends of copper tubes during transportation can lead to microscopic fractures of the metal, which will appear after several months of operation. Compliance with these simple rules will help preserve tightness of the circuit for many years.
Frequently asked questions (FAQ)
Is it dangerous to breathe freon vapors from the refrigerator?
Modern freons (R134a, R600a) in small quantities contained in a household refrigerator (50-150 grams) are not toxic to humans after short-term inhalation. However, they displace oxygen. In a large, unventilated area, a leak may cause suffocation. R600a is also explosive, so ventilation is required.
How much does it cost to refill a refrigerator with freon?
The price consists of the cost of materials (gas, oil, filter) and the work of a specialist in finding leaks and soldering. On average in the market, this can cost from 3,000 to 6,000 rubles and more, depending on the region and the complexity of access to the leak site. The cost of gas in a cylinder itself is low, the main payment is for labor and equipment.
Can freon run out on its own?
No. In a working, sealed system, freon circulates endlessly. If there is less gas, it means that a microcrack or hole has formed through which it escapes into the atmosphere. It cannot simply be “used” or “evaporate” through entire walls.
Why does the refrigerator freeze after refueling, but then stops again?
Most likely, the cause of the leak was not eliminated. The technician could simply add gas without finding the fistula. Over time, new freon will also escape through the same hole. It is also possible that an ice plug may form in the capillary due to moisture in the system if evacuation has not been done.