Diagnostics and replacement compressor is one of the most difficult procedures in servicing household appliances, requiring not only special skills, but also strict adherence to safety precautions. Many owners of units are faced with a situation where the unit stops freezing, hums or is completely silent, which often indicates a failure of this particular unit. Before taking active steps, you need to understand that sealed unit is non-disassembly, and “disassembly” in a domestic context most often means its careful removal from the housing and preparation for disposal or replacement.
Process dismantling is associated with risks, since the refrigerant is under pressure inside the system, and the electrical part is under high voltage. Improper operation may result in personal injury, fire, or damage to other components of the refrigerator. In this article, we will take a detailed look at the algorithm of actions, the necessary tools and nuances that will help you complete the job safely without damaging the copper tubes and electrics.
It is worth noting right away that if your goal is to repair the motor itself (replacing valves or piston group), then it is almost impossible to do this at home without industrial equipment for vacuuming and welding. Therefore, our main focus will be on correctly disconnecting the unit from the system and removing it from the niche. This knowledge will be useful both for replacing parts and for proper disposal of old equipment.
Preparation of the workplace and the necessary tools
The success of any technical operation depends 80% on proper preparation. You will need to clear access to the back of the refrigerator, so make sure that there is at least 1 meter of free space around the unit. De-energizing - This is the first and immutable rule: unplug the power cord from the outlet. Do not rely only on the switch on the case, if it is provided for by the design.
For work, you will need a set of tools, which should be on hand before dismantling begins. Lack of the required key during operation can lead to thread breakage or damage to the pipes. Pay special attention to the condition of the wire insulation, as old refrigerators may have damaged wiring.
- 🔧 A set of open-end wrenches (usually sizes 8, 10, 12 mm) for fastening nuts.
- 🔨 Pliers and side cutters for working with clamps and wires.
- 🔩 Screwdrivers (phillips and flat) of different sizes for removing casings.
- 🧤 Protective gloves (preferably rubberized) to protect hands from sharp edges and oil.
⚠️ Attention: It is strictly forbidden to bite through the copper tubes of the system with wire cutters or squeeze them with pliers until they are completely system discharge. There is gas under pressure inside, which can spray oil or cause a flash if there is a spark nearby.
Prepare a container to collect oil that may leak from the compressor after cutting the tubes. Also have a rag on hand, since the technical oil used in the system is difficult to wash off and has a specific odor. If you are planning to install a new unit, make sure that it fully matches the model of your refrigerator in terms of power and type of refrigerant.
Access to the motor-compressor and removal of the protective casing
The compressor in most modern models (Indesit, Atlant, Bosch) is located in the lower rear part of the case. It is covered with a metal or plastic casing that protects the mechanism from dust and accidental touches. To remove the casing, it is usually enough to unscrew several screws around the perimeter or loosen the fastening bolts.
After removing the protection, you will have a view of the unititself, the capacitor (black grille at the back) and the start-up relay. At this stage, it is important not to jerk the wires and tubes sharply. Carefully inspect the condition of the fasteners: if they are rusty, treat them with a penetrating lubricant (for example, WD-40) and allow time to work so as not to strip the threads when unscrewing.
Often the casing can be secured with special latches. In such models (found in Liebherr or some LGs) there is no need to use brute force. It is enough to pry the edge of the plate with a flat screwdriver and carefully unclip the latches. Remember that plastic becomes brittle over time and can crack from careless movement.
After dismantling the casing, access to the electrical part and pipes will open. Before touching them, make sure once again that the refrigerator is unplugged. The storage capacitor in the start relay can retain charge, so do not touch the contacts with your bare hands right away.
Disconnecting the electrical part and the start relay
The electrical circuit for connecting the compressor is relatively simple, but requires care. The terminal box accepts wires from the thermostat and the start relay. In older models, the wires can simply be twisted and insulated, in new ones they can be connected through plastic blocks.
The first step is to remove the start-up relay. It fits directly onto the compressor terminals (usually three pins). Carefully remove it by pulling it down or to the side, depending on the design. If the relay is fixed with a metal bracket, it must first be bent.
- 📸 Take a photograph of the location of the wires before disconnecting, so that during assembly you do not confuse phase and zero.
- ✂️ If the wires are soldered or heavily oxidized, it is better to carefully bite them, leaving a margin of length on the compressor.
- 🔌 Mark the wires with electrical tape or a marker if you plan to reuse them.
⚠️ Attention: When disconnecting the wires, do not pull on the insulation itself, hold on to the tip or terminal. Old insulation can dry out and peel off, creating the risk of a short circuit in the future.
After disconnecting the electrics, check the integrity of the windings using a multimeter, if possible. This will help diagnose whether the problem is actually in the motor, or whether the relay or thermostat is faulty. The resistance between the contacts must be in a certain range, and there should be no “continuity” to the housing.