The situation when, at the most inopportune moment, the refrigerator stops working, and the ice inside is already beginning to melt, can cause panic in any owner. Often the cause of sudden silence or, conversely, a loud hum is a failure of compressor, which is rightfully considered the “heart” of the entire refrigeration system. If you notice that the unit does not freeze, and the motor does not start or works intermittently, this is the first signal of serious problems with the main unit.
Before sounding the alarm and calling a technician, it is necessary to carry out initial diagnostics to exclude simpler faults, such as lack of electricity or a malfunction in the thermostat. Inverter and conventional motors may behave differently, but the basic principles of testing remain similar for most models, be it Indesit, LG or Beko. Understanding the nature of the breakdown will help you make an informed decision about the advisability of expensive repairs.
In this article we will look in detail at why the engine could burn out, how to distinguish its breakdown from a malfunction of the start relay, and whether it is even worth getting involved with replacing this unit in older models. You will find out what tools you will need to check and whether you can revive the equipment on your own without resorting to the help of a service center.
How to understand that the problem is in the compressor
Diagnostics begins with carefully listening to a working (or trying to work) unit. If you hear a characteristic click followed by silence, or the motor hums for a few seconds and then stops, this indicates that starting relay tries to start the shaft, but is unsuccessful. In normal operation, the engine emits a monotonous, barely audible hum, which does not interrupt spontaneously.
Another sure sign is the body temperature. Touch the rear grille and side walls: if the motor is hot but there is no cold in the chambers, it means that freon is not circulating through the system. This may occur due to the fact that the piston group inside sealed casing is jammed or worn out so much that it does not create the necessary pressure.
⚠️ Attention: If you smell burning or see sparking in the engine compartment area, immediately disconnect the device from the power supply! Further attempts to turn it on may result in a short circuit or fire in the wiring.
You should also pay attention to the light in the camera. If the light is on, it means there is voltage in the socket, and the problem lies within the structure. However, sometimes it happens that the winding of the motor itself burns out, and then the multimeter will show the absence of resistance at the contacts.
Main reasons for motor failure
The service life of a modern compressor is on average 10 years, but aggressive operating conditions can shorten this period. One of the main causes of breakdown is overheatingcaused by a violation of heat transfer. If you haven’t washed the condenser grill at the back for a long time or have moved the refrigerator close to the wall, the motor is working at its limit, trying to gain temperature.
Frequent power surges are also detrimental to the electronics and motor windings. Even if your house has a general stabilizer, sharp impulse surges can damage starting winding. Owners of equipment in districts or the private sector should be especially attentive to the quality of electricity.
- 🔥 Overheating: Dust accumulation on the radiator or poor ventilation around the case.
- ⚡ Power surges: Sudden changes in the network that break through winding insulation.
- 💧 Moisture: Water ingress during defrosting or washing the floor under the engine compartment.
- 🛑 Mechanical wear: Natural aging of piston group parts after 10-12 years of operation.
Often the cause is the refrigerant itself. If there is a leak in the system Freon, the compressor starts working without interruption, trying to compensate for the lack of pressure. As a result, it overheats and burns out. Therefore, before replacing the motor, the technician must check the system for leaks.
Symptoms of malfunction: table of symptoms
To more accurately determine the nature of the breakdown, it is convenient to use the comparison table. Different symptoms may indicate different stages of destruction of the mechanism or related problems with the electrical part.
| Symptom | Probable cause | Difficulty of repair |
|---|---|---|
| The motor hums, but does not start | Piston group jamming or relay failure | High (assembly replacement) |
| Clicks every 2-3 minutes | Faulty start relay or thermostat | Medium (replacement relay) |
| The refrigerator is silent, there is no light | Power circuit is broken or the wiring is burned out | Low (cable check) |
| Extreme heating of the motor housing | Lack of freon or wear compressor | High (refilling + replacement) |
| Loud knocking during operation | Destruction of internal valves or shock absorbers | High (replacement of unit) |
By analyzing this data, you can first understand the scale of the disaster. However, the final verdict is possible only after an instrumental check of the winding resistance.
⚠️ Attention: If you find that the tubes coming out of the compressor have traces of oil, this indicates a depressurization of the system. In this case, simply replacing the motor will not help - you will need a complete refill and search for leaks.
Why can’t you ignore the hum?
If the compressor hums but does not start, it consumes a huge starting current. This can lead to a fire in the wiring inside the casing or melting of the contacts in the socket. Do not leave a faulty device connected to the network in the hope that it will “diverge.”
Checking the compressor with a multimeter
For accurate diagnosis, you will need a household one multimeter. Before starting work, be sure to unplug the refrigerator and get to the compressor contacts by removing the protective cover from the back. The terminals usually contain a starting relay, which must be carefully removed.
Switch the device to resistance measurement mode (Ohms). You need to check three pairs of contacts between the three motor terminals. The normal resistance of the working winding is usually 10-30 Ohms, and the starting winding is slightly less. If the device shows infinity (open circuit) or zero (short circuit), it means the winding has burned out..
It is also important to check the breakdown on the housing. Touch one probe to any contact, and the other to the stripped metal part of the compressor housing. If the multimeter beeps or shows any resistance, the insulation is broken. Operating such a unit is deadly.
☑️ Diagnostics with a multimeter
Do not forget that for inverter models the check may differ, since there the current is converted before being supplied to the motor. They often require more complex diagnostics through the control unit.
Is it possible to replace the compressor with your own hands
Theoretically, it is possible to replace the unit, but in practice this is one of the most difficult procedures in repairing household appliances. To operate, you will need not only a new compressor, but also special equipment: vacuum pump, a pressure gauge station, a torch for soldering copper tubes and a cylinder with freon.
The process involves cutting old pipes, soldering new ones, vacuuming the system to remove moisture and air, and then accurately charging the refrigerant by weight. An error at any stage, for example, moisture getting inside the circuit or improper refueling, will lead to rapid failure of the new motor.
- 🛠️ Tools: You need a pipe cutter, rolling machine, burner and pump.
- 🧪 Chemistry: The exact type of freon is required (R600a, R134a) and oil.
- 🔥 Skills: Experience in soldering copper and working under pressure is required.
If you do not have experience working with refrigeration equipment, attempting to replace it yourself is likely 99% will end in equipment damage. It is better to entrust this task to professionals who will give a guarantee for their work.
The cost of repair or purchase of a new refrigerator
Economic feasibility is the main question that faces the owner. Replacing a compressor is an expensive procedure, consisting of the price of the unit itself, the cost of refrigerant, materials and the work of the technician. On average, repairs cost 40-60% of the cost of a new refrigerator.
If your unit is more than 10-12 years old, it makes sense to think about buying new equipment. Older models are less energy efficient, and a new refrigerator will pay for itself in a couple of years due to energy savings. In addition, no one will give a long-term guarantee for an old unit after a major overhaul.
However, if you have a premium model or a refrigerator built into the kitchen unit, repairs may be a more profitable solution than rehanging the furniture and buying an analogue. In the case of simple economy class models, repairs often do not make sense.
⚠️ Attention: Prices for services and spare parts may vary depending on the region and exchange rates. Before starting work, be sure to request a final estimate from the specialist to avoid unpleasant surprises.
Frequently asked questions (FAQ)
How long does it take to replace a compressor?
A qualified technician will perform the replacement within 1.5–2 hours. This time includes dismantling the old unit, soldering the new one, evacuation of the system and refilling with freon. However, waiting for a technician and delivery of spare parts may take from 1 to 3 days.
Is it possible to restore a burnt-out compressor?
At home - no. The sealed casing is not intended to be opened. Attempts to drill holes and weld them lead to loss of tightness and reliability. Only some industrial units can be restored, but not household ones.
Why does a new compressor get hotter than the old one?
Modern motors often operate at higher housing temperatures to increase efficiency. If the temperature does not exceed 80-90 degrees and there is no burning smell, this may be normal. However, severe overheating may indicate problems with the condenser or an excess of freon.
Is the operation of the refrigerator guaranteed after replacement?
Professional services provide a guarantee for compressor replacement from 6 to 12 months. It is important to receive an official certificate of completion of work and a receipt. The warranty does not cover power surges and mechanical damage after repair.