A sudden stop of the refrigerator often becomes an unpleasant surprise, especially when there are perishable foods left inside. One of the common causes of failure is clogging of the refrigeration circuit with oxidation products, moisture or oil residues. In such cases, simply replacing parts is not enough - a complete flushing of the entire system is required.
The procedure for cleaning pipelines is necessary after combustion compressor or when moisture is detected in the circuit. If you ignore this step, the new unit may fail after a few months of operation. Properly performed flushing freon pipes extends the service life of equipment and ensures stable cooling.
In this article we will analyze the technical nuances of the process, the necessary tools and chemical compositions. You will learn how to safely remove stains and avoid repeated breakdowns. It is important to understand that working with refrigerants and high pressure requires compliance with safety measures.
⚠️ Attention: Flushing the system requires professional equipment and skills in working with tools under pressure. Incorrect actions can lead to depressurization of the circuit or damage to components.
When flushing the refrigeration circuit is necessary
The need to clean the system can be determined by a number of indirect signs and diagnostic results. Most often, the need for the procedure arises after compressor combustion. In this case, the combustion products of the windings and decomposed oil are spread throughout the entire circuit, clogging narrow passages.
Another reason is moisture getting inside the system. This can happen if the vacuum is poorly vacuumed or the circuit is left open for a long time. Moisture reacts with refrigerant and oil, forming acid, which destroys insulation and metal parts.
- 🔥 Complete or partial combustion of the compressor motor winding.
- 💧 Ingress of atmospheric moisture into the circuit during long-term repairs.
- 🛑 Detection of black sediment or emulsion in the filter drier.
- 📉 Reduced unit performance without visible freon leaks.
If, when opening the system, you find that the oil in the compressor has darkened or has a burning smell, flushing is required. Ignoring this fact will result in the new unit working in an aggressive environment. Acidic residues will quickly disable it.
Necessary tools and chemical compositions
For high-quality cleaning refrigeration system a specialized set of tools will be required. The basic element is a cylinder with dry nitrogen. It is the inert gas that allows you to create the necessary pressure to blow out contaminants without the risk of oxidation of the internal walls.
The second important component is the solvent. There are various options on the market, but the most effective is liquid propane-butane (in special cylinders) or specialized liquids such as "Antimore". The use of gasoline or acetone is strictly not recommended due to the risk of damage to rubber seals and the formation of carbon deposits.
| Tool/Material | Purpose | Application features |
|---|---|---|
| Nitrogen cylinder | Creating pressure | Pressure is regulated by a reducer up to 10-15 atm |
| Solvent (R11, R141b) | Dissolving oils | Poured into the circuit under nitrogen pressure |
| Burner | Soldering of tubes | Necessary for sealing after flushing |
| Vacuum pump | Moisture removal | Used at the final stage |
You will also need a pressure gauge manifold, hoses for vacuuming and soldering, as well as a new filter drier. The filter is a consumable item and is installed every time after washing. Its task is to retain any remaining moisture and acids that may have remained in the system.
⚠️ Attention: Technical requirements for refrigerants and oils may vary depending on environmental standards. Always check the compatibility of the selected solvent with the type of freon and oil used in your refrigerator.
Preparing the refrigerator for the cleaning procedure
Before starting active operations, it is necessary to properly prepare the unit. First of all, the refrigerator is disconnected from the power supply and defrosted. All products must be removed, and the internal chambers must be washed and dried.
The next step is to dismantle the old compressor if it has burned out. The tubes coming from the motor are cut, and the unit itself is removed from the frame. This opens access to discharge and suction pipes. It is through them that the main flushing will be carried out.
☑️ Preparation for flushing
It is important to visually assess the condition of the tubes. If oxides or impurities are visible on the cut, they should be cleaned. You also need to decide whether you will flush the entire system or remove the condenser and evaporator separately. For deep cleaning, it is better to use separate washing each element.
Nitrogen and solvent washing technology
The cleaning process itself is based on alternating the supply of solvent and purging with dry gas. First, a small amount of special liquid is poured into the circuit. Then the system is sealed, and nitrogen is supplied through the manifold at a pressure of about 10-15 atmospheres.
The sharp expansion of the gas creates a “pneumatic shock” effect, which effectively strips oil deposits and solid particles from the pipe walls. The mixture of solvent and dirt flows from the opposite side into the prepared container. The procedure is repeated until the flowing liquid becomes clear.
- 🌬️ Blow the circuit with pure nitrogen to remove large particles.
- 🧪 Pour 50-100 ml of solvent into the system.
- 💨 Create pressure with nitrogen again for mixing and pushing.
- 👀 Control the color of the emerging stream - it must be clean.
Pay special attention capillary tube. This is the narrowest element of the system, which gets clogged first. If regular blowing does not help, you can try to clean the capillary with a thin wire or replace it with a new one, since washing it is often difficult.
Replacing the filter-drier and assembling the system
After successful washing of all elements, the assembly stage begins. A critically important point is to install a new filter-dryer. The old filter, even if it looks intact, is already saturated with moisture and acids that it previously absorbed.
The filter is installed immediately after removal from the sealed package. The time of its contact with atmospheric air should be minimal (no more than 5-10 minutes), otherwise it will begin to absorb moisture from the air, which will negate all previous work. Soldering of the filter is done quickly so as not to overheat its body.
The vacuum process follows. The pump is connected to the system and a deep vacuum is created for 30-60 minutes. This is necessary to remove solvent vapors and residual moisture. Only after this the system is charged with refrigerant.
Typical errors and safety measures
Violation of the washing technology can lead to serious consequences. One common mistake is using compressed air from a compressor instead of nitrogen. Ordinary air contains moisture, which, if it enters the system, will cause corrosion and the formation of ice plugs.
Another mistake is insufficient vacuuming time. If solvent vapors are not completely removed, they will mix with the oil and change its properties. This will lead to deterioration of the compressor lubrication and possible wedge of the mechanism.
⚠️ Attention: Work in a well-ventilated area. Solvent and refrigerant vapors can be toxic and heavier than air. Avoid open flames near pressurized cylinders.
Excessive pressure should also be avoided when purging. Although copper pipes can withstand high loads, old welds or areas thinned by corrosion may not be able to withstand a sudden surge in pressure. Always monitor the readings pressure gauge.
Frequently asked questions (FAQ)
Is it possible to flush the refrigerator system without nitrogen?
Theoretically, you can use compressed air, but this is highly not recommended. The air contains moisture which will cause corrosion within the system. Nitrogen is an inert and dry gas, which makes it the only safe option for creating pressure during cleaning.
What is better to wash: gasoline or a special solvent?
You cannot use gasoline (especially leaded) as it leaves carbon deposits and destroys rubber products. It is necessary to use special solvents for refrigeration equipment, such as R11, R141b or their modern analogues, which do not leave traces and are compatible with oil.
Do I need to flush the system if I am only changing the compressor?
If the old compressor has burned out, flushing is required. Winding combustion products scatter throughout the entire circuit. If the replacement is planned and the compressor was in good condition, it is enough to replace the filter-drier and perform a vacuum.
How can you tell that the system has been flushed well enough?
The criterion for high-quality flushing is the transparency of the flowing liquid and the absence of black sediment on a white napkin placed under a stream of gas. Also, after assembly and startup, the suction and discharge pressure must correspond to the passport data.