The situation when the refrigerator stops coping with its direct responsibilities often takes you by surprise. Products begin to quickly deteriorate, condensation appears on the walls or, conversely, a “fur coat” freezes, and the inside of the chamber becomes warm. These are sure signs that the system refrigerant circulation is broken or operating with critical failures. In such a situation, it is necessary to act quickly so as not to lose food supplies and prevent failure of expensive components of the unit.
The first thing to do is to carry out initial visual and sound diagnostics. Often the reason lies not in a complex breakdown of electronics, but in trivial things: incorrectly set temperature, clogged ventilation holes or a door that is not tightly closed. However, if you hear that compressor it is humming continuously, but there is no cold, or, conversely, the motor is silent, although it should be working, we are talking about more serious malfunctions. Understanding the principles of operation of the refrigeration circuit will help you more accurately describe the problem to the technician or, in some cases, fix it yourself.
In this article we will analyze in detail the main reasons for the decrease in the performance of the refrigeration unit. We will consider both simple operating errors and complex technical malfunctions that require the intervention of specialists.
Seal failure and operating rules
Before you panic and look for service center contacts, it is worth eliminating the human factor. Very often, users themselves create conditions under which the refrigerator cannot reach the desired temperature. The most common mistake is loading the chamber with warm food. If you put a pot of hot soup inside, thermostat you will keep the compressor on for hours, trying to cool the volume, but the efficiency will be extremely low.
The condition of the rubber seal on the door is also critically important. Over time, it dries out, cracks, or simply becomes contaminated with grease and crumbs. Through microscopic gaps, warm air from the room constantly enters the chamber. As a result, the system works non-stop, but cannot stabilize the climate. Check the tightness of the seal: clamp the sheet of paper with the door and try to pull it out - if it slides freely, the seal is broken.
⚠️ Attention: Never leave the refrigerator door open longer than necessary to load food. Prolonged contact with warm air leads to a sharp jump in humidity and the formation of an ice crust on the evaporator, which blocks heat exchange.
Do not forget about the location of the unit. If the refrigerator is located close to the wall or in a niche without a gap for ventilation, the radiator on the rear wall cannot effectively transfer heat. Heat transfer is broken, the pressure in the system increases and performance drops. Make sure there is free space around the case according to the manufacturer's instructions.
Problems with the No Frost defrosting system
In modern models with the system No Frost or Low Frost the process of removing moisture and defrosting evaporator is automated. If the refrigerator freezes slightly, but the inside of the chamber is dry and there is no obvious ice, the problem may lie in the defrost system components. The main element here is Defrost heating element, which turns on on a timer and heats the evaporator, melting frozen frost. If the heating element is burned out, the ice does not melt, but grows, gradually turning into a monolithic block.
This ice mass blocks the ventilation channels through which cold air should enter the chamber. As a result, the fan circulates air inside the technical compartment, but it does not enter the refrigerator compartment. The user sees the fan running and hears noise, but there is no temperature. It also often fails defrost sensor, which does not give a command to turn on or off the heater at the right time.
For diagnostics, it is necessary to partially disassemble the back panel of the freezer (in two-compressor models) or the common evaporator. Visually, you will see either a “coat” of ice, or, conversely, the absence of ice when the compressor is running, which indicates a freon leak, which will be discussed below. The integrity of the heating element and sensors is checked using a multimeterether in dial-up mode.
☑️ Diagnostics of the No Frost system
It is important to consider that in some models the electronic control module is responsible for the defrosting process. If the relays on the board burn out, the heating command simply does not arrive. In this case, it is necessary to resolder the board elements or completely replace it.
Refrigerant leak and clogged capillary tube
If you hear that the compressor is working (humming), but there is no cold in the chambers at all, or the freezer is working, but it is warm in the refrigerator compartment, there is a high probability freon leaks. The refrigerant circulates in a closed circuit, and if a microcrack has formed somewhere (often in the foamed part of the housing or in welding areas), the gas gradually escapes. Without a sufficient amount of freon, heat is not removed, and the temperature rises.
The second common option is clogged capillary tube. Oil circulates in the system, which can oxidize over time, or moisture enters the circuit, which freezes in a narrow place in the tube, forming an ice plug. The pressure in the system is disrupted: it is high at the compressor outlet and low at the evaporator. Freon cannot effectively boil and absorb heat.
| Symptom | Probable cause | Characteristic symptom |
|---|---|---|
| The compressor is humming, cold no | Freon leak | The evaporator is clean, without frost |
| The freezer is freezing, the upper compartment is not | Capillary clogged | The lower part of the condenser is hot, the upper - cold |
| The compressor turns on for 10-20 seconds and turns off | Malfunction of the start relay | A click is heard, then silence |
| The refrigerator freezes weakly, inside humid | Thermostat malfunction | The compressor does not turn off for hours |
⚠️ Attention: Self-filling the refrigerator with freon is impossible without special equipment (vacuum pump, pressure gauge station, scales). An attempt to “re-gas” the system through the Schrader valve without evacuation will lead to mixing of refrigerants with air and moisture, which will completely destroy the equipment.
Why can’t you just add freon?
Only pure refrigerant should circulate in the system. If a leak occurs, it means the seal has been broken. Simply adding gas will not fix the hole. Moreover, air and moisture will enter the system along with the gas, which will cause an acid reaction with the compressor oil and blockage of the capillary. First you need to find the leak, solder it, vacuum the system and only then refill strictly by weight.
Faults of the compressor and start relay
The heart of the refrigerator is compressor. If it doesn't work, there will be no cooling anywhere. However, a silent engine does not always mean its death. Often the problem lies in the start-up relay. This is a small plastic block that fits over the compressor contacts. Inside there is a coil and contacts that burn or stick over time. As a result, the motor does not receive an impulse to start.
If the relay is working properly, but the compressor hums, clicks and immediately turns off (thermal protection is triggered), this may indicate an interturn short circuit of the windings or a mechanical wedge of the piston group. In such cases, the engine tries to start, consumes huge current, heats up and shuts down. Operating a refrigerator in this mode is dangerous - it can burn out the wiring in the apartment.
Modern inverter compressors work differently. They do not make loud clicks when starting, but gradually gain momentum. If an inverter refrigerator stops cooling, the reason often lies in the inverter control module itself, which stops supplying the correct voltage to the motor windings. Diagnostics of such systems requires special knowledge and instruments.
Failures in the operation of electronics and thermostats
In older models of refrigerators, the mechanical one is responsible for the temperature thermostat. This is a device with a capillary tube that senses cold. If the thermostat is stuck in the off position, the compressor will never start. If it is “stuck” when turned on, the refrigerator will freeze until it turns the food into ice blocks, ignoring the set mode.
In modern models with electronic control (Full No Frost, two-chamber with a display), the role of a thermostat is performed by temperature sensors (thermistors). They change their resistance depending on the heat. If the sensor is lying (shows that the chamber is -5°C, although it is +10°C), the “brains” of the refrigerator will not turn on the compressor. Often such sensors fail due to changes in temperature and humidity.
It is also worth mentioning the control module. Power surges in the network can damage the board elements responsible for switching the compressor or defrost heating element. Visually, traces of burning, swollen capacitors or blackened traces may be visible on the board. Repairing the board is often more economically feasible than replacing the whole unit, but requires the qualifications of a radio engineer.
The influence of seasonality and external factors
Many users forget that a refrigerator is a heat pump that is sensitive to ambient temperature. If you take your old refrigerator out onto an unheated balcony in winter or it is in a garage where the temperature drops below +10°C, it may stop freezing. The oil in the compressor thickens, and the freon cannot condense effectively. Some models have a “Vacation” function or work in a wide climate class, but most household appliances are designed for the range from +16°C to +32°C.
In the summer the situation is the opposite: if the kitchen is +35°C, the refrigerator will work at its maximum capacity. The condenser (grid at the back) may not have time to cool down, especially if the room is stuffy. In such conditions, the unit may freeze worse, and this is normal for its technical characteristics. Try not to place the refrigerator next to the stove, oven or radiators.
When you need to call a technician
You can independently fix problems with door sealing, defrosting, cleaning the condenser and replacing the thermostat (in mechanical models). However, there are situations when you cannot do without a specialist. If you need to open a foamed circuit, search for a freon leak, replace a compressor, or repair an electronic module, it is better to entrust this to professionals. These works require special tools, materials and knowledge.
In addition, inept intervention can lead to more expensive damage. For example, bending of copper tubes when trying to get to the heating element or damage to the insulation of wires. If you are not confident in your abilities, saving money on calling a technician may backfire.
⚠️ Attention: When working with the electrical components of the refrigerator, always disconnect the device from the network. Even after being disconnected from the socket, a life-threatening charge may remain in the capacitors of the control board. Let the equipment stand for 10-15 minutes before starting work.
Frequently asked questions (FAQ)
Why does the refrigerator freeze but does not turn off?
Most often this indicates a freon leak (the system cannot reach the temperature and runs constantly) or a malfunction thermostat/sensor that does not give a signal to stop the compressor. It is also possible that the door seal may be damaged.
Can the refrigerator be used if it is on its side?
It is strictly forbidden to turn on the refrigerator immediately after transporting it on its side. Oil from the compressor may have leaked into the freon circulation circuit. It is necessary to let the unit stand upright for at least 4-8 hours (preferably a day) so that the oil flows back into the engine crankcase.
How often do you need to defrost a No Frost refrigerator?
The No Frost system does not require manual defrosting to remove ice, as this happens automatically. However, it is recommended to completely turn off the refrigerator 1-2 times a year, wash it and let it dry to eliminate odors and carry out sanitation.
Why is there water on the floor in the refrigerator?
Most likely, the drainage hole for draining melt water is clogged. It is located on the back wall inside the camera. It can be cleaned with a special soft wire or a brush, and then rinsed with warm water using a syringe.