The situation when the refrigerator stops cooling always takes you by surprise, threatening food spoilage. Most often, the culprit of the malfunction is compressor the heart of the unit, which ensures the circulation of the refrigerant. However, before calling a technician or buying a new motor, you need to be sure of the diagnosis, since the symptoms can be deceiving.
The silence of the refrigerator or, conversely, its excessive noise can indicate various problems: from a burnt winding to a banal sticking of the start relay. In this article, we will analyze in detail how to understand what exactly compressor has failed, and what indirect signs will indicate the need for serious repairs.
It is important not to ignore the first signals of a malfunction. If you notice that Indesit or Atlant are behaving uncharacteristically, it is worth conducting an initial diagnosis. Understanding the physics of the process will help you save time and money by avoiding unnecessary expenses on repairing other components.
Complete absence of engine noise and vibration
The most obvious sign that compressor is not working is absolute silence where there should be a smooth hum. A working refrigerator cycles on and off, creating background noise. If you put your ear to the back wall and did not hear any sounds of the motor operating, although the indicators are on, this is an alarming signal.
The absence of vibration on the body of a running unit also speaks volumes. During operation, the engine creates microvibrations that are transmitted to metal tubes and walls. If the housing is cold and completely static, the electrical circuit may be broken or the winding has burned out.
It is worth checking whether voltage is being supplied to the unit at all. Sometimes the problem lies not in the motor itself, but in the supply wires or the thermostat, which simply does not give the command to start. In such cases starting relay may be working properly, but the start signal is not received.
⚠️ Attention: If the refrigerator is completely de-energized, the absence of noise is normal. Make sure that the power cord is working properly and there is voltage in the outlet before sinning on the motor.
For accurate diagnostics of the electrical part, it is better to use a multimeter. A winding test will show whether there is a break inside the motor coils. If the device shows infinite resistance, then compressor most likely it has burned out and requires replacement.
However, motor silence can also be caused by protective automation. If the system detects a critical error, it will block startup to prevent a fire. In models with electronic control Error Code it can suggest a specific reason for the blocking.
Characteristic clicks when trying to start
A frequent symptom of a malfunction is a rhythmic clicking sound coming from the back of the refrigerator. These sounds are produced by starting relay, which is trying to start the motor, but encounters resistance. A click means that current is being supplied, but the engine cannot reach the required speed.
If you hear a series of clicks with an interval of 10-20 seconds, this indicates that the relay is triggered, the engine hums for a split second and immediately stalls. This situation often occurs when the piston group is jammed or an interturn short circuit in the windings.
- 🔌 Sticking of contacts in the starting relay does not allow the circuit to close completely.
- 🔨 The jamming of the piston inside the compressor requires mechanical intervention or replacement.
- ⚡ Voltage drop in the network may prevent the motor from developing the required power to start.
In some cases, replacing the start relay helps if it is compressor still viable. This is an inexpensive part that you can replace yourself with basic skills. However, if after replacing the relay the clicks continue, the problem is deeper.
Long-term operation in constant clicking mode is dangerous. It leads to overheating of the windings and can finally finish off a still serviceable engine. Therefore, when such sounds appear, it is better to stop using the refrigerator.
The motor hums, but does not start
The situation when compressor makes a long humming sound, but does not start, is classic. The motor is trying to turn the shaft, but a mechanical obstacle or lack of starting torque prevents it from doing so. The hum can last from several seconds to minutes.
With this operating mode, the current in the windings increases significantly, which leads to rapid heating of the motor housing. If you touch the motor (be careful, it may be hot!), it will be hot. This is a sign that the thermal protection relay is triggered, opening the circuit.
The reasons for this behavior often lie in the mechanical part. The piston group could wear out or suffer water hammer if liquid gets into the system. It is also possible that the shaft bearings may become jammed due to oil leakage or contamination.
Is it possible to start a jammed compressor?
There is a method of “swinging” the compressor by applying voltage directly, bypassing the relay. However, this is dangerous and requires qualifications. At home, there is a high risk of completely burning the windings or getting an electric shock. It is better to entrust this to professionals.
If the humming is accompanied by the smell of burning or scorched insulation, this is a bad sign. Most likely, the insulation of the windings has already been damaged and must be irrevocably replaced. It is impossible to operate such a unit. compressor subject to irrevocable replacement. This unit cannot be used.
Sometimes humming occurs due to problems with the refrigerant. If there is critically little freon in the system or it has all been released, the compressor runs “idle”, trying to create pressure that cannot exist. This also leads to overheating and stopping.
Lack of cooling when the motor is running
It happens that compressor works smoothly, without extraneous sounds, but there is no cold in the chambers. This may indicate that the motor is not producing the required pressure. The compressor may hum, but not pump freon through the system.
This situation often occurs when the piston rod inside the sealed housing breaks. The motor rotates, there is vibration, but there is no mechanical transmission of force to the piston. This cannot be determined visually; the unit must be opened or replaced.
A refrigerant leak may also be the cause. If a hole has formed in the system, compressor it simply distills gas in a circle or pumps air without creating the required temperature difference. Check the tubes for oily stains - this is a sign of a leak.
| Symptom | Probable cause | Action |
|---|---|---|
| Humming, but not starts | Stuck, relay malfunction | Replacement of relay, motor diagnostics |
| Works, but does not cool | Freon leak, broken rod | Search leaks, refueling, compressor replacement |
| Complete silence | Winding break, no power | Disconnection with a multimeter, circuit check |
| Gets very hot | Overload, wear | Emergency shutdown, repair |
It is important to distinguish between the operation of the motor in normal mode and in overload mode. If the refrigerator hums constantly without turning off, and the temperature inside does not drop below +10°C, it means it is not doing its job. This may be due to a loss of performance. compressor fails to cope with its task. This may be due to loss of productivity.
In inverter-controlled models, the lack of cold when the motor is running may indicate a control board error. The inverter may send incorrect signals that prevent the motor from reaching operating speed.
Overheating of the compressor housing
The normal operating temperature of the compressor housing is 50-60°C. If the hand cannot withstand touching for more than 2-3 seconds, it means the engine is overheating. This is a direct sign that compressor the compressor is overloaded or its resource has been exhausted.
Overheating is often accompanied by a change in the color of the paint on the motor casing (it may turn black or yellow). A specific smell of heated metal or burnt insulation may also appear.
The causes of overheating can be external: contamination of the condenser (grids at the back), poor ventilation, installation of the refrigerator close to the wall. In such cases, the motor does not have time to cool down in the pauses between cycles.
Internal causes of overheating are more serious. Wear of rubbing parts leads to friction and heating. If the oil in the system has lost its properties or has become small, the lubrication deteriorates and compressor begins to “suffocate” from the temperature.
Prolonged overheating leads to degradation of the winding insulation. Sooner or later a short circuit will occur and the motor will burn out. Therefore, monitoring the body temperature is an important element of prevention.
Diagnostics and checking the electrical part
To confirm the diagnosis of what exactly is not working compressorit is necessary to measure the resistance of the windings. For this you will need a multimeter. Before starting work, be sure to unplug the refrigerator!
Remove the protective casing from the compressor and get to the contact group. Usually there are three outputs: two working and one common. Call pairs of contacts. The resistance should be between 10-30 ohms. If the device shows one (infinity) - an open circuit, if zero - a short circuit.
- 📉 Interturn closure difficult to detect with a conventional tester, you need a special device.
- 🔌 Checking the relay is carried out by testing its contacts in different positions.
- ⚡ Starting current is measured with current clamps and must correspond to the passport data.
It is also worth checking whether the motor “breaks through” the housing. One probe of the multimeter is placed on the contact, the other on the copper tube or body. The device should show infinity. If there is any resistance, it means that the insulation is broken and operation is dangerous.
⚠️ Attention: Carry out all electrical diagnostic work only with the device disconnected from the network. Residual voltage in capacitors can be dangerous.
If you are not confident in your abilities, it is better not to take risks. Incorrect diagnosis may result in electric shock or further damage to equipment. In difficult cases, professional equipment is required.
☑️ Compressor diagnostics
Frequently asked questions about compressor malfunctions
Is it possible to repair a burnt-out compressor?
At home - no. Compressor It is a sealed unit, and its disassembly requires special equipment and skills. Usually the unit is completely replaced with a new or refurbished one.
How much does it cost to replace a compressor?
The price consists of the cost of the motor itself and the work of the master. On average, this ranges from 30% to 60% of the cost of a new refrigerator. For older models, repair may not be economically feasible.
Why does the compressor turn on and then immediately turn off?
This is a thermal protection relay triggered. The motor cannot start due to a mechanical obstacle, jamming or problems with the starting winding, it heats up and shuts down abnormally.
Is it dangerous to use a refrigerator with a faulty compressor?
Yes, it can be a fire hazard. Overheating of the windings, sparking of the relay or breakdown of insulation can lead to a fire. In addition, food will spoil due to the lack of cold.
How to extend the life of a new compressor?
Do not place the refrigerator near the radiator, defrost regularly (if there is no Frost), do not load a lot of warm products at once and keep an eye on the cleanliness of the condenser at the back.