The situation when the refrigerator stops freezing and the compressor works without stopping or, conversely, is silent, often puts the owner before a choice: call a technician or try to fix the problem yourself. Replacing freon (refrigerant) is a technically complex process that requires not only theoretical knowledge, but also specialized equipment. Many users underestimate the risks associated with leakage refrigeration circuit, which can lead to the final failure of expensive equipment.
Before taking active steps, you must clearly understand: refrigerant circulates in a closed system under pressure, and its leakage indicates depressurization. You cannot simply “add gas”, as is done in car air conditioners, in household refrigerators Indesit, Atlant or LG the system requires complete evacuation of air and moisture. The most common cause of leakage is corrosion of the evaporator pipelines (“crying” circuit) hidden in the walls of the chamber.
If you decide to do your own repairs, you will have to become a bit of a technical engineer. You will need not only a new gas cylinder, but vacuum pumpa gauge station, a soldering torch and leak detection tools. Ignoring any of the stages, especially evacuation, is guaranteed to lead to rapid repeated failure of the unit due to blockage of the capillary tube with moisture or oxidation products.
Diagnostics of the leak and preparation of the tool
The first step is always to confirm the diagnosis. If the compressor is running, but there is no cold, and there is no characteristic uniform cooling on the rear grille or inside the chamber, there is a high probability of lack of refrigerant. However, before cutting the tubes, make sure that the compressor itself is not clogged and is working properly. A visual inspection can often help locate the location of corrosion, especially at the bottom of the freezer or in the foamed space near the evaporator. capillary tube and the compressor itself is working properly. A visual inspection can often help locate corrosion, especially in the bottom of the freezer or in a foamy area near the evaporator.
You will need to assemble a serious arsenal of equipment to carry out the work. Without special tools, it is impossible to perform high-quality refueling, since the creation of a deep vacuum and precise pressure control are required. R134a and R600a (isobutane) require a different approach and different equipment for refueling.
- 🛠️ Manometer station (manifold) with hoses for the appropriate type freon.
- 🔌 Vacuum pump capable of creating a residual pressure of no more than 50 microns.
- 🔥 Gas burner (oxygen-propane or with flux) for soldering copper tubes.
- 🧪 Leak detector or soap solution for checking the tightness of the connections.
⚠️ Attention: If you find that a leak has occurred in the foamed part of the housing (the evaporator is frozen into the wall), replacing the circuit yourself requires the highest skill. In 80% of cases, it is easier and more reliable to install an external mounted evaporatorthan to open the case.
Safety precautions and choice of refrigerant
Working with refrigerants is associated with certain risks for the health and safety of the premises. Most modern refrigerators run on R600a (isobutane), which is a flammable gas. The concentration of this gas in the air, combined with a spark from the compressor relay or static electricity, can lead to micro-explosion. Therefore, the room where the work is being carried out must be ideally ventilated, and any sources of open flame (except for the burner during soldering) must be eliminated.
The choice of freon type depends on the model of your refrigerator. Typically, information about the type and amount of refrigerant is indicated on a label located on the back wall or inside the chamber. Using the wrong gas or violating the proportions (if a mixture is used) will lead to incorrect operation of the thermostat and overload of the compressor. Dosage must be accurate to the gram, since modern systems are critical to the amount of substance.
When working with open fire and metal, care must be taken not to damage the plastic elements of the housing or wiring The burner flame should be directed strictly at the soldering area, and it is better to shield adjacent areas with a metal plate.
Dismantling old equipment and troubleshooting
The process begins by disconnecting the refrigerator from the network and moving it to free space. It is necessary to gain access to the compressor compartment. The first step is to bleed off the remaining gas if there is still pressure in the system. To do this, carefully break the thinnest tube - usually a capillary or outlet from the filter drier. A characteristic scroll will indicate the presence of residual pressure.
Next, you need to remove the old filter drier. This element is responsible for absorbing moisture, which inevitably accumulates in the system upon contact with air. Reusing the old filter strictly prohibitedas its sorbent is already saturated and will not be able to protect the system from the formation of ice plugs. The filter is cut off, and a plug or a new filter can be temporarily installed in its place for the evacuation stage.
At this stage, nitrogen pressure testing is often carried out to find the location of the leak, if it has not been found visually. Nitrogen is supplied to the system under a pressure of about 10-15 atmospheres, after which all connections and suspicious areas are lubricated with a soap solution. The appearance of bubbles will indicate microcrack or a fistula.
Why can’t you use oxygen for pressure testing?
Oxygen mixed with oil in the compressor forms an explosive mixture. The slightest spark or heating can cause a powerful explosion, so only dry nitrogen is used for refrigeration equipment.
Soldering pipelines and installing a new filter
Soldering copper pipes is a skill that requires practice. Copper melts easily, so it is important not to overheat the material. The tubes are cleaned to a shine, solder is applied to them, and the joint is heated with a torch. It is important that no oxides remain inside the tube, so professionals often flush the system with nitrogen during the soldering process, displacing oxygen.
After all leaks have been eliminated, a new filter drier is installed. It must be soldered as quickly as possible to minimize contact of the sorbent with atmospheric air. The direction of flow in the filter is indicated by an arrow on the housing - you cannot make a mistake here, otherwise the system will not work. After cooling, all connections are again checked for leaks.
| System element | Function | Replacement is required? | Risk if ignored |
|---|---|---|---|
| Filter drier | Removal of moisture and acids | Yes, always | Clogging of capillary with ice |
| Compressor | Freon circulation | Only in case of breakdown | No cold |
| Capillary tube | Throttling (pressure reduction) | If clogged | Improper refrigerant boiling |
| Evaporator | Heat removal from the chamber | With corrosion | Constant leak |
The quality of soldering directly affects the durability of the repair. If the seam is porous, the gas will begin to escape gradually, and after a few months history will repeat itself. Therefore, after the seam has cooled, it should be inspected through a magnifying glass: it should be smooth, without holes or solder deposits inside the tube.
Vacuuming the system
This is the most critical stage, which amateurs often perform formally or skip. Evacuation is necessary to remove not only air from the system, but also, more importantly, water vapor. Water in the refrigerator system freezes in the capillary tube, forming an ice plug that blocks the circulation of freon. In addition, moisture reacts with oil and freon, forming aggressive acids that corrode the metal from the inside.
The process is as follows: a hose from the vacuum pump is connected to the service fitting (which you most likely installed to replace the cut tube). The pump turns on for a long time. For household refrigerators, the minimum operating time of the pump is 30-40 minutes, and for systems with R600a - up to an hour. The pressure should drop to the minimum values that the pump is capable of.
- 💨 Connect the vacuum pump to the service port.
- ⏱️ Turn on the pump and leave it running for at least 40-60 minutes.
- 🔒 Close the valve on the manifold without turning off the pump, and monitor the pressure gauge arrow.
- 👀 If the arrow creeps up, there is a leak in the system that needs to be found.
⚠️ Attention: Never try to “blow out” the system with your own compressor or your mouth! Introducing moisture and dirt from the lungs or ordinary air is guaranteed to kill the refrigerator. Only a vacuum pump!
☑️ Checking readiness for vacuuming
Filling the refrigerator with freon
After successful vacuuming, the moment of refueling comes. The freon cylinder must be upside down (if the liquid phase is being charged, which is faster) or stand normally (the vapor phase, longer and more accurate). For accuracy, it is better to use electronic scales. The valve on the cylinder opens, and the refrigerant is released into the system in small portions.
The process needs to be controlled by two parameters: the weight of the charged substance and the pressure in the system (although pressure is an indirect parameter and depends on the ambient temperature). The compressor must be started at this moment. The correct amount of freon is indicated by uniform cooling of the evaporator and the absence of freezing of the suction tube of the compressor (it should be slightly cool, but not frosted).
If you overdo it with gas, the compressor will work with overload, and the cooling efficiency will drop. If you don’t fill it enough, the refrigerator will not freeze. After reaching the desired weight, the service tube is clamped with a special clamp and sealed. This must be done quickly so that the vacuum does not have time to suck in air.
Checking performance and tightness
The final stage is testing. The refrigerator is left on for several hours. Normally, it should reach temperature and turn off according to the thermostat. If used No Frost, the operation of the fan and defrost system is checked. It is important to make sure that after stopping the compressor there is no hissing, indicating gas etching.
The soap solution is applied to all new seams and joints again, this time under operating pressure. Particular attention is paid to the place where the service tube is soldered. It is also worth listening to the operation of the compressor: it should not hum too loudly or vibrate, which may indicate water hammer (liquid freon entering the cylinder due to an overdose).
If all stages are completed successfully, the refrigerator will return to normal operation. However, it is worth remembering that refueling yourself is a risk. The lack of a guarantee and the possibility of error make this path suitable only for those who are ready to take responsibility for the result.
How to understand that there is little freon if there is no pressure gauge?
If there is a shortage of freon, the condenser (grid at the back) will be heated up only 30-50% of its length, and the rest will remain cold. At normal temperatures, the entire radiator is warmed up.
Is it possible to fill the refrigerator with freon from a can for refilling air conditioners?
Absolutely not. Automotive freons (R12, R134a in aerosols) often contain oils and additives that are incompatible with your compressor oil. In addition, it is impossible to control the exact weight in such cylinders, and refilling “by eye” will lead to breakdown.
How long does the freon replacement procedure take?
For an experienced technician, the process takes 1.5–2 hours. For a beginner, taking into account leak detection, soldering and waiting for vacuuming, this can take half a day or more. Take your time, rushing here is fraught with defects.
Why, after replacing freon, does the refrigerator freeze, but does not turn off?
Possible reasons: an overdose of freon, a blockage in the filter or capillary, or a malfunction of the thermostat itself. Also, the cause may be poor-quality evacuation when there is an air lock in the system.
Is it necessary to change the oil in the compressor when replacing freon?
In the standard procedure for eliminating leaks, the oil is not changed if the compressor is working. An oil change is required only when the compressor burns out or if a large amount of moisture and acids have entered the system, which is determined by analyzing the oil for acidity.