The situation when it is warm inside the refrigerator compartment, food begins to spoil, and the compressor continues to hum monotonously, is one of the most common and frightening breakdowns. It seems paradoxical: the motor is running, there is electricity, but the cooling effect is completely absent. This is a sure sign that refrigerant circulation is broken or the control system did not work correctly, blocking the normal cooling cycle.
Before calling a technician or looking for a new unit, it is important to conduct an initial diagnosis to understand the scale of the problem. Often the reason lies not in the fatal breakdown of expensive components, but in a banal gas leak or valve sticking. In this article, we will analyze in detail the mechanics of the process so that you can understand why your Refrigerator refrigerator has stopped performing its main function.
Ignoring the problem can lead to a complete stop of the compressor, which, running idle without proper cooling or under constant load, will simply burn out. Therefore, if you notice that the unit is humming, but does not produce cold, you need to act quickly and competently.
The principle of operation and why the cold disappears
To understand the essence of the malfunction, you need to briefly remember how the cooling cycle works. The compressor compresses the gas, turning it into a high-pressure liquid, which then passes through the condenser (grid at the back), releasing heat into the room. Next, the refrigerant enters the evaporator inside the chamber, where it expands sharply and boils, taking heat from the products. freon, turning it into a high-pressure liquid, which then passes through the condenser (grid at the back), releasing heat into the room. Next, the refrigerant enters the evaporator inside the chamber, where it expands sharply and boils, taking heat from the products.
If the engine is running, but there is no cold, then this vicious circle is broken. Physically, the compressor can create pressure, but if there is no working fluid (gas) in the system or it cannot circulate due to blockage, heat exchange does not occur. In this case, the motor simply pumps gas inside itself or idles.
Modern models, such as Indesit or Atlant, are often equipped with a No Frost system, where cold air is pumped by a fan. If the fan is broken or the evaporator is frozen, the compressor will work, trying to cool the chamber, but the air simply will not circulate.
⚠️ Attention: Prolonged operation of the compressor without shutting down (more than 24 hours) in the absence of cold indicates that the automation does not receive a signal that the desired temperature has been reached. This is a direct path to overheating and a jam of the motor.
It is important to distinguish between situations when the refrigerator freezes weakly and when there is no cold at all. In the first case, there may be a problem with the door seal, in the second, we are talking about serious technical malfunctions.
Refrigerant leak: the most common cause
The most common reason that the refrigerator hums but does not cool is a banal freon leak. The refrigerant circulates through thin tubes, and over time, microcracks can form in welds or bends. Since freon is a gas, it simply evaporates into the atmosphere without leaving a trace.
When the amount of gas in the system drops below a critical level, the compressor continues to work, trying to create pressure, but there is simply nothing to cool. You may notice that the motor is running longer than usual or without stopping at all, trying to compensate for the lack of cold.
Leakage can occur due to:
- 🕰️ Corrosion of metal tubes, especially in older models where steel was used instead of copper.
- 🔨 Mechanical damage during transportation or carelessness defrosting (piercing the evaporator with a knife).
- 🏭 Factory defect in soldering connections, which appears after several years of operation.
It is difficult to diagnose a leak on your own, since the gas is colorless and odorless. However, an indirect sign may be the absence of heating of the condenser on the sides of the case or on the back grill - they should be warm or hot.
Clogged capillary tube
The second most popular reason is clogged capillary tube. This is a very narrow section of the line where a sharp drop in freon pressure occurs. Over time, oil oxidation products, moisture or small chips can accumulate in the system, which creates a plug.
As a result, the compressor pushes gas, but it cannot pass through the narrow opening. The pressure before the plug increases, and after it, it drops to a vacuum. Circulation stops and cold is no longer produced. Often, you can hear that the engine is working with a strained hum or periodically clicks the thermal protection relay.
Symptoms of a blockage are often confused with a leak, but there are differences:
- ❄️ When clogged, the filter drier (cylinder near the compressor) may become covered with frost or, conversely, severely heat up.
- 🔊 The sound of the operating compressor may be duller or intermittent.
- 🌡️ The condenser may heat up unevenly: hot at the beginning and cold after the blockage.
To eliminate this problem, you need to call a technician who will flush the system with special nitrogen under pressure and will replace the filter drier.
⚠️ Attention: Attempts to clean the tube yourself without a vacuum pump and special tools will only lead to moisture getting into the system, which will completely damage the compressor.
Compressor malfunctions
Although The compressor is the “heart” of the refrigerator; its breakdowns occur less frequently than leaks, but they are more critical. If the engine hums but does not start (you can only hear a hum and clicks), the piston group may be jammed or the winding may be burned out.
In some cases, the compressor works, but it is worn out. The pistons pump, but do not create the required compression (pressure). The gas simply circulates in a circle inside the motor housing without entering the cooling system. Visually, this looks like normal engine operation, but the tubes at the outlet and inlet have the same temperature. valve group worn out. The pistons pump, but do not create the required compression (pressure). The gas simply circulates in a circle inside the motor housing without entering the cooling system. Visually this looks like normal motor operation, but the outlet and inlet tubes have the same temperature.
Checking the compressor requires measuring the pressure with a pressure gauge. If there is no powerful pressure of gas at the outlet of a running engine, then its resource has been exhausted.
Comparison of symptoms of different breakdowns:
| Symptom | Freon leakage | Clogged system | Compressor malfunction |
|---|---|---|---|
| Motor operation | No stops | With overload or cyclically | Humming, clicking or idling |
| Condenser temperature | Cold or barely warm | Hot at the beginning, cold further | Can be hot |
| Frost in the chamber | Absent | Can be locally at the outlet | Absent |
| Solution | Search for leaks, refueling | Purge, replace filter | Replacing the compressor |
Is it possible to replace the compressor yourself?
Theoretically, yes, if you have the skills to solder copper pipes and work with electricity. However, this requires a vacuum pump, a burner, a pressure gauge station and precise knowledge of the amount of freon to be charged. Without experience, there is a high risk of ruining a new expensive unit.
Problems with the control module and sensors
In modern models, such as Samsung or LG, the electronic control module is responsible for the operation of all components. If it receives incorrect data from temperature sensors, it may not send a command to turn on the compressor or, conversely, not turn it off.
A malfunction of the evaporator temperature sensor is often encountered. If it “lies” and shows that it is already -30°C in the chamber, the control module simply will not start cooling, although it may be +10°C inside. In this case, the engine may not work at all or operate on a shortened cycle.
It is also worth checking:
- 🔌 The integrity of the wiring going from the door to the body (often breaks).
- 🧊 State of the defrosting heating element (if the refrigerator is No Frost and filled with ice).
- 🌀 Operation of the blower fan (if it does not spin, the cold will not enter the chamber).
Diagnostics of electronics is carried out using a multimeter and requires knowledge of circuitry. Often the module requires flashing or replacing burnt-out elements.
Features of two-compressor systems
In refrigerators with two compressors (separately for the freezer and refrigerator), the situation can be local. If only one chamber does not freeze, and the other is working normally, then the problem is in the circuit of the non-working section.
This narrows the search: a leak or blockage occurred in only one of the circuits. The compressor of the faulty chamber will work constantly, trying to gain temperature, while the second motor will turn on and off as normal.
In such cases, repairs may be more economically feasible, since it is often possible to temporarily isolate the faulty circuit, maintaining the operation of the second chamber, although a full repair is still preferable.
What to do first: checklist
Before calling the service, follow simple steps that will help the technician more accurately diagnose the problem over the phone or, possibly, fix the problem without repair.
☑️ Primary diagnosis
Full defrosting is a universal tip. If the drainage in the No Frost system is clogged or the damper is frozen, a day without power can melt the ice plug. If cold appears after switching on, you are lucky; if not, repairs are required.
Also check the tightness of the door. If the seal is worn out or the door is warped, the cold constantly escapes, and the compressor does not have time to compensate for it, working non-stop.
⚠️ Attention: Do not try to open the sealed parts of the system or pierce the tubes yourself. Remaining freon can ignite upon contact with fire, and air entering the system will make repairs much more expensive.
Frequently asked questions (FAQ)
How long does it take for the refrigerator to get cold after defrosting?
Usually the temperature stabilization process takes from 2 to 6 hours, depending on the volume of the chamber and the temperature in the room. Complete freezing of food can take up to 24 hours.
Why does the refrigerator click and not turn on?
Clicks indicate the operation of the start relay or heat sink. Most likely, the compressor is trying to start, but cannot due to a wedge, low voltage in the network or a malfunction of the relay itself.
Is it possible to operate a refrigerator if it does not freeze?
It is strictly not recommended. A running compressor without switching off quickly overheats, the oil in it loses its properties, which leads to an expensive replacement of the entire unit.
How can you tell that a compressor has burned out?
If you hear a hum when you turn it on, after a few seconds there is a click and silence, and the motor housing is very hot - most likely, the winding is burned out or the motor is jammed.