Diagnostics and replacement compressor often become the only way to bring back to life a refrigerator that has stopped freezing. If you hear a hum, but there is no cold, or the unit is silent despite the working light bulb, there is a high probability that the problem lies in the heart of the system. Opening the motor is a complex technical process that requires not only physical effort, but also a specific tool, as well as strict adherence to safety measures.
Before proceeding with dismantling, you need to understand that sealed unit (as the compressor assembly is often called) is not intended for disassembly at home without subsequent professional sealing. However, if your goal is to replace a burned-out assembly with a new one or remove parts for diagnostics, you will have to go through the procedure of disconnecting the copper tubes and electrical parts. It is important to assess your strengths in advance, since the work involves refrigerants and high pressure.
In this article we will analyze in detail how to properly dismantle the unit, what tools will be needed and how to avoid common mistakes that can lead to injury or damage to property. We will look at the nuances of working with different types of fasteners and electrical circuits so that you can complete the job as efficiently as possible.
Preparation of the workplace and the necessary tools
The success of the operation to remove the motor directly depends on the quality of preparation. You will need not just a set of screwdrivers, but also specialized equipment for working with copper lines. Without proper preparation, you risk damaging your pipes or getting burned by hot solder. Pay special attention to lighting and ventilation, as gas may be released during the process.
The basic set of tools should include open-end wrenches of different sizes, pliers, side cutters and powerful wire cutters. To work with copper tubing, it is critical to have a pipe cutter or a quality hacksaw, although professionals prefer pipe cutters to avoid creating chips inside the system. You will also need a gas torch or a special hair dryer for desoldering connections.
- 🔧 Open-end wrenches (8, 10, 12 mm) for dismantling frame fastenings.
- 🔥 Gas torch or blowtorch for heating the solder on the fittings.
- 🧤 Protective gloves and glasses to prevent injury from splashes of oil or metal.
- 🧲 Powerful magnet for collecting small metal particles after cutting pipes.
Particular attention should be paid safety glasses. When copper tubing is bitten or old bolts are removed, small pieces often fly off and can cause serious eye damage. Do not neglect personal protective equipment, even if the work seems simple to you.
⚠️ Attention: Before starting any work, make sure that the refrigerator is completely disconnected from the power supply. Working with electrical appliances under voltage is deadly!
If you plan not just to throw away the old motor, but to troubleshoot it, you may need a pressure gauge station to check the pressure. However, for basic dismantling, a mechanical kit is sufficient. Make sure that you have a container for draining old compressor oil, as it is waste and requires disposal.
☑️ Preparation for dismantling
Access to the compressor and removal of the protective casing
The first stage of work is to gain physical access to the bottom of the refrigerator. In most modern models compressor located in a niche in the lower rear part of the case. To get to it, you need to carefully remove the back metal or plastic panel. Usually it is attached with self-tapping screws around the perimeter.
After removing the panel, you will see a black metal tank - this is the compressor casing. It protects the mechanism from dust and moisture, and also reduces noise levels. The casing can be secured with latches or bolts. Be careful: the edges of the metal after factory stamping are often sharp, so you need to work with thick gloves.
There are two main types of casing fastening:
- 🔩 Bolted connection: you need to unscrew 2-4 bolts with a wrench.
- 🔘 Latches: you need to carefully release them flat with a screwdriver, without applying excessive force.
After removing the casing, you will see itself compressor with copper tubes and an electrical unit (start-up relay) suitable for it. It is important not to yank anything sharply at this stage, as the tubes can become fragile from time and vibration. Visually inspect the condition of the pipes and the presence of traces of oil, which may indicate a leak.
Why are casings often rusty?
Compressor casings often become rusty due to condensation that forms when temperatures change. If the rust is superficial, this is not a problem, but through holes require replacing the casing or painting it with heat-resistant enamel.
Disconnecting the electrical part and the starting relay
Before touching the copper lines, you must completely de-energize the electrical circuit. At the end of the compressor there is a plastic box in which the contacts are hidden. Remove the cover of this box and you will see the starting and protective relay mounted on the motor rod.
Carefully remove the relay from the rod. They are usually held in place by a tight fit and fixing brackets. Do not pull on the wires; grasp the plastic housing of the relay directly. After dismantling the relay, it is necessary to disconnect the wires coming from the refrigerator. To do this, use side cutters or wire cutters, cutting the wires as close to the relay block as possible to leave some extra length on the main cable.
| Component | Function | Location |
|---|---|---|
| Start relay | Starts the engine by supplying current to the starting winding | On the side of the rod |
| Thermal relay | Protects against overheating by opening the circuit | Often combined with starting |
| Capacitor | Smoothes starting currents (not in all models) | Next to the relay or inside the casing |
It is important to remember or photograph the wiring diagram before disconnecting them if you plan to use the old relay for testing or installation into a new compressor. Color markings may vary between manufacturers, such as Atlant, Beko or Indesit.
Unsoldering copper tubes and removing the unit
The most critical stage is working with the refrigeration circuit. Two copper tubes are connected to the compressor: one high pressure (discharge, usually hot during operation) and one low pressure (suction, cold). The third tube is a process fitting (filling), which is often sealed or plugged.
To disconnect the tubes, you need to heat the soldering area with a gas torch. The flame should be directed at the solder, and not at the tube itself, so as not to burn the copper. When the solder becomes liquid and flows, gently pull the tube. If it doesn't work, warm up the connection a little more. Sudden movements can break the tube at the very base of the compressor, which will complicate further work.
During the desoldering process, residual freon and oil may come out of the pipes. Keep in mind that the oil may be hot and have a distinct odor. Place the prepared container under the unsoldering point. After disconnecting all the tubes, the compressor will remain hanging only on rubber shock absorbers or metal studs.
- 🌡️ Heat the connection evenly on all sides.
- 🛑 Do not allow the insulation of the wires to overheat if they are nearby.
- 💨 Provide ventilation, as flux combustion products can be harmful.
After disconnecting the lines, unscrew the mounting bolts holding the compressor to the refrigerator frame. Usually there are four. Remove the unit, being careful, as the weight of the motor can reach 10-12 kg. When lifting, hold the compressor vertically to prevent oil from entering the circulation system if you plan to reuse it (although this is rare).
⚠️ Attention: It is strictly forbidden to open the sealed compressor housing (cut with a grinder) in a closed room without an exhaust hood. There may be gas under pressure inside, and when heated, residual oil may ignite.
Nuances of working with different types of compressors
The design of the motors may vary depending on the manufacturer and year of manufacture of the refrigerator. Inverter compressors, which are becoming increasingly popular in models LG and Samsung, have a fundamentally different control system and are often mounted differently than classic piston units.
Classic motors have a rigid suspension inside the casing or an external spring suspension. When removing the latter, it is important not to lose the springs and rubber bushings, as they dampen vibration. If the springs are stretched or deformed, it is better to replace them, otherwise the new or repaired motor will make a lot of noise.
Inverter models often do not have a starting relay in the usual form, since the rotation speed is controlled by an electronic unit. Dismantling such systems requires greater care with electronics. In addition, in some modern models, the tubes can be argon welded rather than sealed with tin, which requires more powerful equipment for opening.
Pay attention to the markings. The compressor nameplate indicates important parameters: refrigerant (R134a, R600a), power and oil type. This information is critical when selecting a replacement. Oil for different types of freon it has a different chemical base (mineral, polyester), and mixing them is unacceptable.
Disposal and precautions
After removing the motor, you are faced with the issue of disposal. An old compressor contains residual refrigerant and technical oil that cannot simply be poured down the drain or thrown into a general trash bin. Refrigerants, especially older types, can be harmful to the environment.
If you open the housing to return metal, do it outdoors. Inside the case there is a copper winding, which is highly valued when delivered to non-ferrous metal collection points. The steel body is also recyclable. However, remember that when sawing the housing there may be high pressure inside, so make the first cut carefully.
Collect the oil from the compressor in an airtight container and take it to a waste oil collection point or dispose of it according to the rules of your region. Oil getting into the soil or water bodies causes serious environmental damage.
| Type of waste | Where to take it in | Danger |
|---|---|---|
| Metal case | Black collection point scrap metal | Low |
| Copper winding | Reception point for non-ferrous metals | Low |
| Compressor oil | Special reception centers, service stations | High (pollution) |
| Freon residues | Specialized services | Medium (asphyxiation, fire) |
In conclusion, I would like to note that replacing the compressor yourself is a task for advanced craftsmen. If you do not have experience in soldering copper pipes and evacuating the system, it is better to limit yourself to dismantling and call a specialist to install a new unit and refill with freon.
Is it possible to repair an old compressor?
In 95% of cases, repairing a hermetic compressor is not economically feasible. The cost of overhaul, replacement of valves and vacuum sealing often exceeds the price of a new analogue, and the service life of the restored unit is unpredictable.
Do the tubes need to be cut off or can they be unscrewed?
In 99% of cases, the tubes are soldered or welded. They cannot be unscrewed. The only option for disconnecting without soldering is cutting with a pipe cutter or metal scissors, but to completely remove the compressor from the frame you will still need to solder or cut in an accessible place.
Is it dangerous to release freon during dismantling?
Modern freons (R134a, R600a) in small quantities quantities found in a household refrigerator are not toxic on short-term contact, but R600a (isobutane) is explosive. Therefore, you need to work in a ventilated area and away from open fire until the gas has completely evaporated.
Why is the compressor hot after work?
The normal operating temperature of the compressor housing can reach 70-90 degrees Celsius. This is due to gas compression and friction of mechanical parts. If the motor heats up to a state where it is impossible to touch with your hand (more than 100-110°C), and then turns off, this is a sign of a malfunction.
Is it possible to replace the compressor with an analogue from another company?
Yes, it is possible if the main parameters match: power (or cylinder volume), type of refrigerant, type of oil, overall dimensions and landing holes. For example, Danfoss compressors are often replaced with Secop or Atlant, subject to technical conditions.