Sudden defrosting of food and lack of cold in the chambers is a stressful situation for any home cook. If you notice that the freezer has stopped freezing, and the compressor is humming continuously, but does not start or is running idle, most likely the system has depressurized. It is this technical term that means that refrigerant physically left the closed circuit and evaporated into the atmosphere.
Many users mistakenly believe that the gas can simply “run out” over time, like water in a jug, but this is not the case. In a serviceable, sealed circuit freon circulates for decades without the need for refueling. A situation where a substance has “leaked” somewhere always indicates the presence of a hole, a fistula or a crack in the tubes through which gas under pressure has escaped.
You can independently understand that a leak has occurred by a number of indirect signs that appear long before the complete loss of cold. It is critical not to ignore the first symptoms, as running the compressor without proper cooling (which is provided by circulating freon) can lead to costly combustion. Below we will look in detail at why this happens and how to act in such a situation.
How a sealed cooling system works
To understand why a leak occurs, it is necessary to understand the basic structure of the refrigeration unit. This is a closed system of metal tubes through which it circulates under pressure refrigerant. In normal condition, there are no valves for releasing gas, as, for example, in a car air conditioner, where scheduled refueling is possible. The entire system is sealed at the factory and is designed for the full service life of the product.
The movement of the substance is provided by a compressor, which compresses the gas, turning it into liquid, and pushes it through the condenser. There, giving off heat, freon again becomes a gas and passes through evaporator, where the chambers are cooled. Any violation of the integrity of this path, be it a microscopic crack in the solder or through damage to the housing, leads to an instant loss of pressure.
⚠️ Attention: Freon is odorless and colorless in the gaseous state. You will not be able to sense its leak by the smell of gas (the smell can only come from burnt insulation or oil), so you cannot rely on your senses when searching for a hole.
It is important to note that the system also circulates compressor oil, which is mixed with freon to lubricate the rubbing parts of the motor. When gas escapes, drops of oil are often released along with it under pressure. It is oily stains on the floor or on the back wall of the refrigerator that are the most reliable indicator of the location of the leak.
The pressure in the system may vary depending on the brand of gas used and the ambient temperature, but it is always higher than atmospheric. This means that when a hole appears, the gas tends to go out and does not suck air in (although with prolonged idle and complete evacuation, moisture can penetrate, which is a separate serious problem).
Mechanical damage: the most common cause
The statistics of service centers are inexorable: more than 60% of cases where freon is lost are associated with the careless actions of the owners themselves or movers. Mechanical damage to the integrity of the evaporator or tubes is a direct path to depressurization. Most often, models with an open evaporatorlocated directly in the freezer, without a protective plastic box, suffer.
The classic situation occurs during defrosting. Many people still use sharp objects (knives, screwdrivers, ice picks) to chip ice. One awkward move and the blade pierces the thin aluminum wall of the evaporator. A characteristic hissing sound at this moment indicates that the gas is actively escaping, taking with it oil particles.
In addition, mechanical damage can be caused during transportation or installation of equipment. If you moved the refrigerator and touched the tubes located on the back wall, or hit the case hard in the freezer area, the integrity of the circuit could be compromised. In modern models with the system No Frost tubes are often hidden in polyurethane foam, which makes them less vulnerable to a knife, but does not protect them from strong impacts.
Sometimes the cause is metal corrosion. If the refrigerator is used in a humid room or water constantly condenses on its back wall, the metal becomes thinner. Over time, microscopic holes appear on the condenser tubes, especially in places of soldering or bends, through which the gas slowly but surely evaporates.
Manufacturer defects and soldering defects
Even new refrigerators just bought in a store are not immune to problems with tightness. Factory defects are less common than mechanical damage, but they cannot be completely excluded. Most often, defects lie in the quality solders connections of copper tubes. If during assembly at the factory the technology was violated or low-quality solder was used, a fistula may form at the joint.
Such leaks often appear in the first year of operation. Gas may escape very slowly, so the user may not immediately notice a decrease in performance. At first, the refrigerator simply begins to take longer to restore the temperature after opening the door, then the compressor operating intervals increase, and eventually it stops turning off altogether.
Another reason for the factory nature may be the use of low-quality metal for the manufacture of evaporators. In pursuit of cheaper production, some brands use aluminum alloys that are susceptible to galvanic corrosion. This is especially true if moisture has entered the system or incompatible metals have been used in the connecting nodes.
It is almost impossible to diagnose manufacturing defects on your own without special equipment. However, if the refrigerator is new, has not been subjected to impacts or defrosting with blunt objects, and the cold has disappeared, the likelihood of a manufacturing defect is high. In this case, you must contact the warranty service, since repairs under warranty should be free.
Corrosion and a “crying” circuit
There is a specific type of leak associated with circuit corrosion, which is often called a “crying” circuit. Along the perimeter of the doorway of the freezer there is a tube with hot freon (the so-called heating circuit), which prevents the formation of condensation and freezing of the door. Due to constant contact with moisture and an aggressive environment, these areas are often subject to corrosion.
Rust eats the metal inside and out, forming through holes. This process is lengthy and can take several years. The owner may not suspect for years that a problem is brewing in the refrigerator wall, until one day the system completely loses pressure. A characteristic sign is a rusty leak in the lower part of the case or on the floor under the refrigerator.
The danger of this situation is that repairs often require complex work to replace part of the circuit or install an external capacitor, since it is not always possible to properly seal a hole in the foamed part of the case. Modern models are becoming more and more vulnerable to this, as the thickness of the metal tubes is decreasing.
Why can’t you leave the refrigerator in an unheated room?
During the cold season, the oil in the compressor thickens, and moisture from the air, entering the system due to possible microcracks, freezes. This can lead to water hammer during startup or blockage of the capillary tube, which is not formally a freon leak, but disables the equipment.
Diagnostics: how to find the leak location
If you are faced with the problem of lack of cold, the first thing you need to do is localize the place where the freon left. Professional craftsmen use leak detectors (electronic gas detectors) or the soaping method. At home, you can try a visual inspection, although it is only effective if there are obvious oil stains.
For an accurate search, technicians use nitrogen. The system is pumped with nitrogen under high pressure and immersed in water or lubricated with a soap solution. Air bubbles will indicate the location of depressurization. Ultraviolet diagnostics are also used if a phosphor was previously added to the system, but this is rare for household repairs.
Below is a table that helps classify signs and possible locations of a leak:
| Symptom | Probable cause | Location location |
|---|---|---|
| Oil stain on the floor | Mechanical breakdown, corrosion of the bottom | Lower part of the body, foaming |
| Ice coat in one corner | Microcrack in the evaporator | Inside the freezer cameras |
| Rust on the tubes at the back | Natural metal corrosion | Rear wall, condenser |
| Lack of cold after defrosting | Breakdown knife/screwdriver | Rear wall of the freezer |
It is important to understand that finding a leak is a labor-intensive process that requires equipment. Just “smell” or “listen” to the refrigerator is not enough. Often the gas outlet point is in the foamed part of the case, which makes it inaccessible for simple visual inspection without opening the thermal insulation.
Consequences of working without refrigerant
Many users, having noticed that the refrigerator has stopped freezing, continue to operate it, hoping for a miracle or trying to “reanimate” it with a low temperature in the room. This is a big mistake. Idle operation of the compressor, without circulating freon, which also serves as a cooler for the motor windings, leads to critical overheating.
In the best case, the thermal protection relay will work and the motor will turn off. In the worst case, a breakdown of the winding insulation will occur and the compressor will burn out. Replacing a compressor is an expensive procedure that is often not economically feasible compared to purchasing new equipment. In addition, when the engine burns, combustion products enter the system, which then have to be thoroughly washed out.
⚠️ Attention: If you hear a click and a hum, but the cold does not go for more than 2-3 hours, immediately unplug the device. Continuing work can finish off a compressor that is still working.
It is also worth remembering the environmental aspect. Although modern freons (R600a, R134a) are less harmful to the ozone layer than their predecessors (freon R12), their release into the atmosphere is still undesirable. Isobutane (R600a), used in most modern refrigerators, is also explosive in high concentrations in a confined space.
Repair: sealing or replacing the circuit?
When the cause is found, the question of repair arises. If the damage is localized in an accessible place (for example, the evaporator in the chamber is broken), the technician may suggest soldering the hole. However, for aluminum evaporators, conventional tin soldering is not suitable - special argon welding or the use of chemical reagents is required, which does not always give a durable result.
Often a more reliable, albeit expensive option, is to install a new one (a “crying” plate or box) instead of repairing the old one. If the leak occurs in the foamed part of the housing (inside the walls), repair becomes extremely difficult. Craftsmen may suggest cutting off the rotten section and removing the external condenser, attaching it to the back of the refrigerator with silicone suction cups. evaporator ("crying" plate or box) instead of repairing the old one. If the leak occurs in the foamed part of the housing (inside the walls), repair becomes extremely difficult. Craftsmen may suggest cutting off the rotten section and removing the external condenser, attaching it to the back of the refrigerator with silicone suction cups.
After eliminating the physical hole, the system must be evacuated. This is a critically important stage Vacuuming needed to remove air and, most importantly, moisture from the tubes. The moisture in the system freezes in the capillary tube, forming an ice plug that blocks gas circulation, and the refrigerator stops working again.
☑️ Algorithm for action in case of freon leak
Prevention and operating rules
In order to avoid the problem of leakage, you must follow the operating rules. The main thing is to never use sharp objects to remove ice. If an ice crust has formed, let it melt naturally or use special defrosting products that are safe for plastic and metal.
Regularly check the condition of the door seals. A poorly closing door leads to constant ice formation, which increases the frequency of defrosts and, as a result, the risk of mechanical damage. It is also worth periodically inspecting the back wall for blistering paint or signs of rust.
When moving or rearranging, be extremely careful. Do not grab the condenser tubes located at the rear or hit the housing. Remember that the thin walls of the evaporator inside the chamber are the most vulnerable element of the entire structure.
Is it possible to fill a refrigerator with freon on your own?
Theoretically it is possible if you have equipment (gas cylinder, pressure gauges, vacuum pump, burner), but in practice it is extremely difficult and dangerous. Without finding and fixing the leak, refilling will only have an effect for a few days or weeks. In addition, different models require a strictly defined amount and brand of freon, as well as an exact dosage of oil.
How much does it cost to repair a freon leak?
The cost consists of the work of finding the leak, the cost of materials (freon, oil, solder) and the difficulty of accessing the damage site. If you need to replace the evaporator or overcook the foamed circuit, the price can reach 50-70% of the cost of a new refrigerator.
How can you tell that the freon has completely come out?
Main signs: the compressor runs constantly or does not start at all (hums and clicks), both chambers (refrigerator and freezer) are warm, The condenser on the back wall is cold or slightly warm, not hot. There may also be no characteristic gurgling or hissing in the tubes during operation.
Is the released freon harmful to humans?
Modern refrigerants (R600a, R134a) in small quantities contained in a household refrigerator are not toxic to humans during short-term inhalation in a ventilated area. However, R600a (isobutane) is explosive, so if there is a strong leak, it is necessary to ventilate the kitchen and not turn on electrical appliances so that a spark does not cause ignition.
Why does the refrigerator not freeze again after refilling freon?
If after refilling the cold does not appear, it means either the leak was not found and eliminated (gas again gone), either there is moisture left in the system that has formed an ice plug, or the compressor/thermostat is faulty. High-quality repairs always include finding holes and vacuuming.