A decrease in cooling efficiency or a complete stop in the operation of the refrigeration chamber often makes owners think about the condition of the refrigerant. Freon It is the “blood” of the system, circulating in a closed circuit and providing heat removal. In a working device with high-quality assembly, the amount of this gas remains unchanged throughout its entire service life, since it is not consumed during operation.
However, if the question arises “how much freon should there be,” this almost always indicates depressurization of the circuit. Leakage can occur in microscopic portions over the years or happen simultaneously due to mechanical damage. Understanding the principles of operation and precise charging standards is necessary for diagnosing a malfunction and planning repairs.
Modern models operating on isobutane or new types of freons require special accuracy when refueling. An error in calculating the amount of grams can lead to compressor failure or insufficient refrigeration. Therefore, it is important not to guess, but to rely on the manufacturer’s technical data.
The role of the refrigerant and the principle of circulation
The refrigerant is a working fluid that changes its state of aggregation from liquid to gaseous and back, taking thermal energy from the internal chamber of the refrigerator. This process occurs in evaporatorwhere freon boils at low temperatures, absorbing the heat of the products. The movement of gas is ensured by a compressor, which creates the necessary pressure in the system.
After compression, the hot gas enters condenser (usually a grille at the back or panels on the sides of the body), where it releases heat into the environment and turns into a liquid state. The cycle closes when the liquid, through capillary tube or the choke, again enters the evaporator, where the pressure drops sharply and the boiling process is repeated. Violation of the amount of substance in this vicious circle breaks the entire thermodynamics of the process.
If there is less freon in the system than required, the suction pressure will drop, the compressor will work for wear, trying to gain temperature, but will not be able to provide proper cooling. Excess will lead to hydraulic hammer, since liquid freon can get into the compressor, which is fatal for its mechanical part.
⚠️ Attention: Freon is colorless and odorless (except for some brands with an additive), so it is impossible to visually detect its leak in the air without special equipment or soap solution.
Refill rates and types of refrigerants
The answer to the question of how many grams of freon is needed completely depends on the model of the refrigerator, the volume of the chambers and the type of gas used. Manufacturers do not adhere to a single standard “by eye”, but calculate the volume based on the heat capacity of the specific refrigerant and size of the heat exchangers.
In older models, R12 was often used, which required relatively large volumes. Modern environmentally friendly gases, such as R600a (isobutane), have different physical properties and require significantly less substance to operate effectively. That is why, when switching to new types of gases, filling rates may differ significantly.
Precise information about the type and amount of refrigerant can always be found on the technical sticker located inside the refrigeration chamber or on the back wall of the unit. The factory parameter is indicated there charge, which is the standard for the master.
| Refrigerant type | Chemical formula | Average charging rate (grams) | Features |
|---|---|---|---|
| R12 (Freon-12) | CCl2F2 | 140 - 250 g | Outdated, destroys the ozone layer |
| R134a | CH2FCF3 | 100 - 200 g | More environmentally friendly, high pressure |
| R600a (Isobutane) | C4H10 | 30 - 60 g | Explosive, requires gram accuracy |
| R407C / R410A | Mixtures | 400 - 800 g | Used in powerful systems and air conditioners |
It is important to understand that the table gives only approximate values. The actual figure for your Atlanta or Liebherr may vary. For example, in large-volume two-chamber models the amount of gas can reach 300-400 grams, while in compact single-chamber bars it rarely exceeds 100 grams.
⚠️ Attention: Isobutane (R600a) is a flammable gas. Work to replace or refuel refrigerators using this gas should only be carried out in ventilated areas away from sources of open fire.
Signs of a freon leak in the system
You can determine that the amount of freon in the refrigerator has decreased by a number of indirect signs. The first and most noticeable symptom is insufficient cooling. The products in the chamber begin to deteriorate faster, and the characteristic “fur coat” on the walls may disappear or, conversely, an ice crust may appear in one corner until the rest of the heat is released.
The compressor begins to work almost non-stop, trying to compensate for the lack of cooling capacity. If you touch the motor, it may be hotter than usual, as it is operating in overload mode. In this case, the condenser (grid at the back) may remain barely warm or cold, which indicates a small amount of circulating gas.
In some cases, when the leak occurred suddenly, you can hear a hissing or whistling sound at the site where the tube is damaged. However, most often the process occurs slowly, and the owner notices the problem only when the refrigerator stops freezing completely.
- 📉 The compressor hums continuously, without turning off for rest.
- 🌡️ The temperature in the chamber is higher than the set one, the food is thawed.
- ❄️ An ice crust forms only near the evaporator or is absent altogether.
- 🔥 The side walls or rear grille remain cold when the engine is running.
There is also a visual inspection method that you can apply yourself. If you find oily stains on the floor under the refrigerator or near the compressor, this is almost a hundred percent sign depressurization. Freon circulates in the system along with oil, and the release of oil to the outside is always accompanied by the release of gas.
Diagnostics and search for the location of the leak
Before thinking about the amount of freon to be charged, it is necessary to find and eliminate the location of the leak. Simply adding gas is a temporary solution that will lead to another breakdown in a week or month. Professional diagnostics begin with a visual inspection of all accessible components.
Masters often use leak detectors - electronic devices that capture halogen molecules in the air. This is the fastest way to find even a microscopic fistula. If there is no such device, the old but reliable method with a soap solution is used.
To do this, thick soap foam is applied to suspicious areas (welds, pipe connections, entry points into the housing). If there is pressure left in the system, a bubble will begin to inflate at the leak site. In difficult cases, when a visual search does not produce results, the system is pressed nitrogen under high pressure and immersed in water or special additives are used in the gas to search with ultraviolet light.
⚠️ Attention: Never try to look for a leak with an open flame (lighter), especially if you do not know what type of freon was used previously. The combustion products of some freons are toxic, and in the case of R600a this can lead to an explosion.
Frequent places of leaks are:
- 🔩 Places of tube rolling connections.
- 🛡️ Areas of the “crying” evaporator inside chambers (corrosion).
- 🔧 Area of the foamed door heating circuit (often rots from below).
- ⚙️ Compressor seals (rare, but found on older models).
Why can’t you just add freon?
Adding freon without eliminating the leak is money down the drain. The gas will escape through the same hole in a short time. In addition, if there is a leak, air and moisture could enter the system, which must be removed by vacuuming, otherwise the compressor will burn out.
Refilling process: weighing and control
When the leak is found and repaired (the tube is sealed or replaced), the refueling stage begins. This is the critical moment where the question of “how much” is decided. Refilling “by eye” or based on the operating time of the compressor is the path to unstable operation. The only correct method is weighing.
The master connects the freon cylinder to a high-precision scale. Knowing how many grams should be in the system (based on the sticker), he opens the valve and watches the weight of the cylinder decrease. As soon as the arrow shows that the required amount has entered the system, the supply stops.
For systems using freon mixtures (for example, R407C), it is critical to fill the refrigerant only in liquid phase. To do this, the container is turned upside down. If you fill the mixture in a gaseous state, the proportion of the components will be disrupted and the refrigerator will not work correctly.
☑️ Refilling checklist
After refilling, you need to start the compressor and let the system return to mode. After 15-30 minutes, the consumption currents are checked. If the current is normal and the refrigerator begins to freeze, the process can be considered complete. The capillary tube is finally sealed.
Common mistakes during independent repairs
Attempts to save on the services of a specialist often lead to higher repair costs. The most common mistake is using car air conditioning refill kits. They are not suitable for refrigerators due to the difference in the types of oils and the required dosage accuracy.
The second mistake is ignoring the procedure vacuum. Many people believe that it is enough to simply bleed off the remaining gas and fill in new ones. However, moisture remains in the system, which, when frozen, will clog the capillary, and the acid formed from the reaction of water with oil will destroy the compressor windings.
The third mistake is using the wrong oil. Different types of freons (mineral, synthetic, polyester) require different lubricants. Mixing oils can lead to the formation of solid sediment and breakdown of the compressor.
⚠️ Attention: If you do not have experience working with vacuum pumps and gauge manifolds, the risk of permanently damaging the refrigerator is more than 80%. It is better to entrust this work to a specialist.
Questions and answers (FAQ)
Is it possible to determine the lack of freon without devices?
It is impossible to accurately determine the amount of freon without a pressure gauge. However, an indirect sign is the operation of the compressor without shutdowns and a cold condenser (grid at the back) when the engine is running. If the refrigerator hums but does not cool, most likely there is not enough gas.
How often do you need to change or add freon?
In a working refrigerator, you should never change or add freon never . This is a closed system designed for 10-20 years of operation. If the gas has disappeared somewhere, it means that a hole has formed that needs to be looked for and soldered.
How much does refilling with freon cost?
The price consists of the cost of work on finding the leak, soldering, vacuuming and the cost of the gas itself. This usually accounts for a significant portion of the repair cost. It is difficult to name the exact amount, since it depends on the difficulty of access to the leak site.
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 concentration. In large volumes, any gas displaces oxygen, so in case of a strong leak, it is better to ventilate the room.
Why does the refrigerator freeze worse after refueling?
There may be several reasons: an incorrectly calculated amount of freon (overdosing or underfilling), the presence of air in the system due to poor evacuation, or an unrepaired second leak. It is also possible that the capillary filter is clogged.
What to do if a whistle appears after repair?
The whistle may indicate that there is air left in the system or that the flow area at the soldering site is narrowed. The compressor itself may also whistle when operating at maximum capacity due to improper refueling. Repeated diagnostics are required.