The situation when a household refrigerator works without interruption or does not turn off for too long after being turned on is one of the most common symptoms of a malfunction that equipment owners encounter. In normal operation, the compressor is turned on to build temperature, and then turned off for a long period of rest, waiting for the chamber to heat up. If the motor hums continuously or the operating cycles have been significantly reduced, this indicates that the system cannot achieve the set parameters or temperature control is impaired.
Ignoring this problem can lead to serious consequences, including food spoilage, engine overheating and failure of expensive components. Constant wear and tear reduces the life of the equipment by several times, turning minor adjustments into major repairs. Understanding the nature of such a malfunction will help you react quickly and minimize the damage.
It is important to distinguish between short-term malfunctions and system breakdowns. Sometimes equipment simply adapts to new conditions, but most often the reason lies in a specific technical malfunction that requires intervention. Next, we will analyze in detail the main factors influencing the duration of the compressor operation.
Refrigerant leakage and violation of system tightness
One of the most common reasons why the refrigerator does not turn off is a banal freon leak. The refrigerant is the working fluid of the system, which circulates through the circuit, taking heat from the chambers and releasing it into the environment. If a microcrack has formed in the system, the pressure drops, and the compressor is forced to work in increased mode, trying to compensate for the lack of cooling capacity.
In this case, thermostat does not receive a signal that the desired temperature has been reached, since actual cooling does not occur. The engine operates at the limit of its capabilities, but cannot “catch up” with the cold. A characteristic sign of such a breakdown is that the compressor is hot, but the chambers are warm, or the freezer is working, but the main compartment is not cooling.
⚠️ Attention: If you suspect a freon leak, under no circumstances try to open the pipelines yourself or solder them without special equipment. The refrigerant can be dangerous, and refilling requires evacuation of the system.
Leaks can occur in different places: in the foamed part of the housing, in the evaporator or at the pipe joints. Diagnostics requires the use of a leak detector and a pressure gauge station. Often, owners notice swelling of the back wall inside the chamber or the appearance of oily spots under the refrigerator.
To understand the symptoms, consider the table of signs:
| Symptom | Probable cause | Actions |
|---|---|---|
| The compressor is hot, there is no cold | Freon leak or blockage | Call a technician to find a leak |
| The freezer is working, the refrigerator is warm | Lack of refrigerant | Checking the pressure in the system |
| The refrigerator turns on and immediately turns off | Starting relay or low voltage | Measuring voltage, checking the relay |
| There is a hum, but the motor does not start | Compressor jamming | Replacing the compressor |
If you notice that the equipment has stopped coping with the load, do not delay contacting service. Running "idle" will quickly damage the motor, and repairs will cost much more.
Malfunctions of the thermostat and temperature sensors
The thermostat (thermostat) is the “brain” of the refrigeration chamber, which controls the moment the compressor turns on and off. In older models this is a mechanical device with a capillary tube, in modern ones it is an electronic sensor. If this element fails, it simply stops sending a signal to turn off the motor, even when the temperature inside has already reached the desired value.
As a result, the refrigerator works continuouslycreates excess cold, which can lead to freezing of food in the main compartment. You can check a mechanical thermostat by temporarily shorting its contacts (for diagnostics), but this should be done carefully so as not to damage the electrics. Electronic modules are diagnosed with a multimeter.
Often the problem lies not in the sensor itself, but in a broken contact or displacement of its sensitive part. The capillary tube must fit tightly to the evaporator. If it moves away, the sensor “thinks” that the chamber is warm and causes the compressor to work without stopping.
Replacing the thermostat is a relatively simple procedure, but requires precision. It is important to install a model with similar parameters, otherwise the operating modes may go wrong. In some cases, a simple adjusting the screw on the thermostat body helps, but this requires a professional approach.
Wear of the sealing rubber and loss of tightness
Tight fit of the door to the body is the key to energy efficiency. The sealing rubber (cuff) loses elasticity over time, cracks or deforms. Through the resulting cracks, warm air from the room constantly enters the chamber. The compressor is forced to work without interruption in order to cool this constant flow of heat.
You can check the tightness in a simple way: clamp a sheet of paper between the door and the housing in different places. If the paper falls out or is pulled out without resistance, the seal is broken. Also visually inspect the rubber for cracks, tears and dirt.
If the rubber is simply contaminated with grease or food, it can be washed with warm soapy water. If it becomes dull or torn, replacement is required. In some cases, restoring elasticity using a hairdryer or a special spray helps, but this is a temporary measure.
☑️ Checking the tightness of the refrigerator
Do not forget that a loosely closed door is also the reason for constant operation. The latch mechanism may be weakened, or the refrigerator may be installed at an angle, which prevents it from closing tightly.
Problems with the defrost system (No Frost)
In refrigerators with a system No Frost the serviceability of the automatic defrost system is critical. If the evaporator heating element, defrost timer or thermal fuse fails, a “coat” of ice builds up on the evaporator. This ice blocks the circulation of cold air.
The fan moves the air, but it does not pass through the frozen radiator. Sensors in the chamber detect the high temperature and instruct the compressor to work longer. As a result, the motor hums constantly, trying to break through the ice blockade, but cooling does not occur.
Signs of such a malfunction are often:
- ❄️ Heavy icing of the back wall in the freezer.
- 🔊 Change in operating sound (fan noise or crackling noise ice).
- 🌡️ Lack of cold air from the holes in the chamber.
To solve the problem, complete defrosting (at least 24 hours) and subsequent diagnostics of the elements of the defrosting system are required. Often the heating element or defrost sensor fails and must be replaced.
⚠️ Attention: If you decide to defrost the refrigerator to check, do not use sharp objects to chip the ice. Damage to the evaporator will lead to an immediate leak of freon and expensive repairs.
Incorrect installation and external factors
Sometimes the reason lies not in the breakdown, but in the operating conditions. If the refrigerator is installed too close to the wall, the radiator at the back cannot transfer heat effectively. The air circulates poorly, the condenser temperature rises, and operating efficiency decreases.
The location next to heat sources also affects: radiators, stoves or under direct sunlight. In such conditions, the refrigerator simply does not have time to cool down to the required temperature in a standard cycle.
Check the following installation parameters:
- 📏 The distance to the back wall should be at least 5-7 cm.
- ☀️ No direct sunlight on the body.
- 🔥 Distance from heating devices.
- ⚖️ Horizontal position (adjustment of legs).
Influence of loading with products
If you loaded a lot of warm food into the refrigerator at once or put a large pot of soup, the compressor will work for a long time until it cools the volume. This is fine. Try not to load more than 3-4 kg of food at a time and let it cool to room temperature before placing it in the chamber.
In addition, in the summer, when the room is hot, the refrigerator takes longer to work. This is a natural process associated with the physics of heat transfer.
Wear of the compressor and start relay
The most serious reason is the physical wear of the compressor itself. Over time, the rubbing parts wear out and compression drops. The motor seems to be humming, but does not create enough pressure in the system. It works, but does not “pump.”
Also, the start-up relay often fails. If it is stuck on, the compressor does not receive a command to stop. This can lead to burnout of the motor windings if the problem is not noticed in time.
Signs of compressor wear:
- 🔊 Loud, unnatural knocking or clanging noise during operation.
- 🔥 Excessive heating of the motor housing (impossible touch).
- ⚡ Frequent attempts to start with relay clicks.
Replacing a compressor is a complex and expensive process that requires professional equipment. In some cases, it is more economically feasible to purchase new equipment, especially if the refrigerator is more than 10-12 years old.
Frequently asked questions and answers (FAQ)
How long should the refrigerator operate after being turned on for the first time?
When turned on for the first time or after a long defrosting, the refrigerator may require from 2 to 8 hours to enter operating mode. During this time, the compressor may operate continuously, which is normal. Do not load food during the first hours of operation.
Can low voltage in the network cause continuous operation?
Yes, low voltage can cause the electronics or start relay to not work correctly. The compressor may hum but not start, or may operate intermittently. It is recommended to use a voltage stabilizer if surges in the network are a frequent occurrence.
What to do if the refrigerator does not turn off, but freezes normally?
If the temperature is normal, but the motor does not turn off, most likely the problem is in the thermostat (it is “stuck” or has lost sensitivity) or in a freon leak at an early stage. Pressure diagnostics and checking the thermostat contacts are required.
Is it dangerous to leave a refrigerator running continuously on?
Yes, it is dangerous. Long-term operation without rest cycles leads to overheating of the compressor windings, melting of the insulation and a fire hazard. In addition, this is guaranteed to lead to engine failure. If a problem is detected, it is better to turn off the device until the technician arrives.