The situation when the refrigerator suddenly stops cooling food always takes you by surprise. The owner immediately checks whether the light is on and listens to the sounds of the engine. If there is silence or humming without characteristic vibration, this is the first signal that compressor does not start or is out of order. Understanding what is happening inside the system at this moment will help you avoid fatal mistakes when trying to save products or diagnose a malfunction.
In normal operation, this unit is the “heart” of the unit, creating the necessary pressure for the circulation of the refrigerant. Freon moves in a closed loop only thanks to efforts piston group. When the mechanism stops, the physical process of heat exchange is disrupted, and the temperature in the chambers begins to rapidly rise to room temperature. It is important to clearly understand: without the operation of this unit, the refrigerator turns into an ordinary heat-insulated cabinet.
Many mistakenly believe that cold can be maintained due to residual pressure in the system or inertia, but this is not so. Refrigerant circulation stops instantly after stopping the engine. Next, we will analyze in detail the physics of the process, the symptoms of various types of breakdowns and answer the question whether the equipment has a chance to start working again without expensive intervention.
The role of the compressor in the cooling system
To understand the consequences of a breakdown, you need to briefly recall the principle of operation. The compressor compresses the refrigerant gas, turning it into a liquid under high pressure. This process generates heat, so the rear grille is usually hot. If motor-compressor is faulty, the compression cycle does not start, and the freon remains at rest in one of the sections of the circuit.
In modern models, such as Indesit or LG, it is responsible for starting start protection relay. It supplies an impulse to the motor windings. If the relay is working properly, but the motor is silent, then the problem lies deeper - perhaps the pistons are jammed or the winding is burned out. Without creating a pressure difference between the condenser and the evaporator, it is impossible heat absorption from the internal chamber.
It is worth noting that in two-compressor models, failure of one of the components will lead to loss of cold in only one chamber. For example, if the freezer circuit is broken, the temperature in the refrigerator compartment may remain for some time, but the mode No Frost will stop functioning correctly. The pressure in the system equalizes, and cooling becomes physically impossible.
Symptoms of a complete compressor stop
The first and most obvious sign is the absence of a characteristic hum. A working unit works cyclically: turns on, hums, turns off. If there is dead silence or, conversely, only a quiet hum is heard without vibration of the body, this is an alarm bell. The light bulb inside may be on, which confirms the presence of electricity in the network, but the current does not reach the motor or the motor cannot convert it into movement.
The second symptom is temperature. Food begins to deteriorate, condensation appears on the walls, and ice melts in the freezer. This happens because heat exchange stopped. In models with the system No Frost the fan also stops working, since its operation is often synchronized with the cooling cycle or depends on temperature sensors that record an anomaly.
⚠️ Attention: If you hear a short buzz (2-3 seconds), a click and again silence - This is a sign that the engine is trying to start but cannot. Do not leave the refrigerator turned on for a long time in this state, this can lead to overheating of the windings and a fire.
The third sign is a hot start relay. If you carefully (with the appliance unplugged) touch the box on the side of the compressor, it may be melted or have a burning smell. This suggests that starting current was too large, and the protection worked, breaking the circuit. In this case, the motor itself may be intact, but the system does not allow it to start.
Why the compressor hums, but does not start
The situation when the unit makes sounds, but does not start, is called “humming”. This means that electricity is supplied to the windings, a magnetic field is created, but no mechanical movement of the pistons occurs. Most often, the reason lies in the jamming of the mechanism. Parts inside the case could be worn out, metal debris could get in, or simply “stick” due to overheating.
Another common reason is a faulty start relay. This small element is responsible for switching the windings and starting the rotor. If the contacts in the relay are oxidized or burned out, the engine does not receive the necessary impulse to start. In models Bosch and Samsung relays often fail due to power surges in the network.
It is also worth considering the condition of the electrical wiring. If the cable is broken or the contact in the socket is poor, there may not be enough voltage to create the force necessary to break the piston out of place. However, if the voltage is normal and stays the same, the problem is almost always mechanical or in the relay. rotor stays the same, the problem is almost always mechanical or in the relay.
Diagnostics: electrical or mechanical failure
To determine the type of fault, the technician needs a multimeter. The first step is to check the integrity of the motor windings. The starting, working and common windings are called. If the device shows an open circuit (infinite resistance) or a short circuit (close to zero), then electric motor it has burned out and requires replacement.
If everything is in order with the windings, the starting relay is checked. You can carefully remove it and shake it: if you hear the sound of broken parts inside, the element is faulty. The resistance between the contacts is also checked. In some cases, it helps to temporarily replace the relay with a known good one to check whether the motor will start.
A mechanical wedge is more difficult to diagnose. If the windings are intact, the relay is working properly, there is voltage, but the shaft does not rotate, it means that the compression unit is jammed. Attempts to “unwedge” it with a hammer or by applying increased voltage often give a short-term effect, but the resource of such a unit has already been exhausted. Mechanical wear irreversible.
☑️ Do-it-yourself primary diagnostics
Table of symptoms and probable causes
For ease of data systematization, we present the main scenarios for the behavior of a refrigerator with a faulty compressor. This will help you navigate the situation before the technician arrives.
| Symptom | Probable cause | Necessary actions |
|---|---|---|
| Silence, lamp is on | Open circuit, burnt out relay, winding | Replacing the relay or compressor |
| Buzzing and clicking | Stuck, faulty relay | Attempting to wedge or replacing the unit |
| The motor housing is heating up | Overheating of the windings, interturn short circuit | Urgent shutdown, replacement |
| The refrigerator turns on for 1 minute | Thermal protection | Diagnostics of pressure and compression |
As can be seen from the table, external manifestations may be similar, but the reasons are radically different. For example, overheating can be the result of both poor ventilation and internal damage. Therefore, visual inspection is only the first stage.
Spoiler title
Is it possible to replace the compressor yourself?: Hidden text with details: Theoretically, this is possible if you have the skills to work with a tool and a soldering iron. However, this requires a vacuum pump, a freon scale, and a torch. Without sealing the system and the correct amount of refrigerant, the refrigerator will not work.
Is it possible to temporarily use a refrigerator without a compressor
Short answer: no, it cannot be fully used. Without a working compressor, the refrigerator does not produce cold. However, if one of the two compressors in a two-chamber refrigerator breaks down, the second chamber will continue to operate normally. In single-compressor models, the loss of cold will be complete.
Some users try to use a disconnected refrigerator as a heating cabinet, placing food with ice there. This only makes sense for a very short time (a few hours), since the thermal insulation of household models is not designed for long-term storage without an active refrigeration generator. The temperature inside will quickly become equal to room temperature.
⚠️ Attention: Do not try to connect the refrigerator through timers or breakers to “rest” the motor. If the compressor is broken mechanically, such manipulations will not help, but will only aggravate the situation.
If the breakdown occurs in winter, you can temporarily take the food out to the balcony (subject to negative temperatures), but this is risky for the equipment itself if there are residual oil or liquid in it. It is best to organize temporary storage in a neighbors refrigerator or purchase dry ice.
Repair or replacement: economic feasibility
Repairing the compressor as such (opening, replacing valves, pistons) in a domestic environment is impossible and economically infeasible. Manufacturing plants, such as Whirlpool or Haier, do not supply spare parts for internal repairs of motors. The only option is to completely replace the unit with a new or refurbished one.
The cost of replacement consists of the price of the compressor itself, the cost of the refrigerant, consumables and the work of the technician. In older models, the cost of repairs can reach 70-80% of the cost of a new refrigerator. In this case, it is more logical to think about buying new equipment that will be more energy efficient and quieter.
However, for modern and expensive models, replacement is the only way to extend the life of the device. It is important to choose a compressor of the same power and size as the original. Installing a more powerful or less powerful analogue will lead to incorrect operation of the system and rapid failure of new parts.
How long does the refrigerator keep cold after a breakdown?
The time it keeps cold depends on the load of the chambers and the ambient temperature. A fully loaded refrigerator maintains temperature for up to 8-12 hours. Empty - only 2-4 hours. The door cannot be opened at this time.
Can the compressor start working on its own after cooling?
If the reason was overheating of the thermal protection, then after cooling (30-60 minutes) the refrigerator may start. But if this happens again, it means that the problem has not gone away, and it is dangerous to start the device again.
Is it dangerous to touch the compressor while it is running?
You can touch a running compressor, but be careful. It can be very hot (up to 80-90 degrees). The danger is electric current, so do not touch any live wires or terminals.
Why might a new compressor fail to start?
Reasons: incorrect amount of freon, presence of air in the system (poor vacuum), faulty start relay, faulty capillary tube or incorrect electrical circuit connections.
Does a broken compressor hum?
Yes, often a broken compressor hums louder than usual or makes a metallic clang. Silence when the light is on is also a sign of a breakdown in the electrical part of the motor or relay.