The constant hum of a working unit is the first signal that a failure has occurred in the cooling system. Refrigerator compressor is the heart of the device, and its continuous operation indicates that the equipment cannot reach the set temperature. In normal mode, the motor operation cycle alternates with periods of rest, which saves energy and extends the life of the equipment.
If you notice that refrigerator it hums for days on end, and inside the chamber the temperature is higher than normal or, conversely, food begins to freeze, you cannot ignore this. Long-term wear and tear leads to overheating of the motor windings, deformation of the piston group and, ultimately, to expensive repairs or complete replacement of the unit. A critical sign is the heating of the compressor housing to a state where it is impossible to touch it with your hand.
Before calling technicians, it is necessary to carry out initial diagnostics to eliminate common operating errors. Often the reason lies not in a breakdown of electronics or freon, but in a violation of the seal of the chamber or improper installation of equipment. Understanding the principles of operation refrigeration circuit will help you quickly navigate the situation.
Violation of the tightness and thermal insulation of the chamber
The most common reason for the continuous operation of the motor is the intake of warm air from the outside. If sealing rubber the door is worn, dirty or damaged, the seal is broken. The refrigerator tries to compensate for the loss of cold by running the compressor in continuous mode. Heat can also penetrate through microcracks in the body or a loosely closed door.
Check the condition magnetic seal along the entire perimeter of the door. There should be no stuck grease, crumbs or food debris that would prevent a tight seal. If the rubber has lost its elasticity and become rigid, it ceases to perform its function, allowing warm air to pass inside the chamber.
⚠️ Attention! If the seal is simply dirty, it can be washed with warm water and soap. If the rubber is cracked or torn from the base, a complete replacement of the part will be required to restore the tightness.
To check the tightness of the seal, you can use a simple test with a sheet of paper. Clamp the sheet with the door in different places around the perimeter. If the paper is removed easily, without resistance, it means that in this place seal it is broken and requires adjustment or replacement.
Malfunctions of the thermostat and sensors
Thermostat is responsible for the cycle of turning the engine on and off. This device measures the temperature inside the chamber and sends a signal to open the circuit when a specified threshold is reached. If the thermostat fails and its contacts are “stuck” in the “on” position, the compressor will work constantly, without receiving a command to stop. thermostat (thermostat). This device measures the temperature inside the chamber and sends a signal to open the circuit when a specified threshold is reached. If the thermostat fails and its contacts are stuck in the "on" position, the compressor will run continuously without receiving a command to stop.
In modern models with electronic control, instead of a mechanical thermostat, temperature sensoris used, transmitting readings to the control module. Failure of this sensor or a break in the wiring leads to the fact that the “brains” of the refrigerator do not receive up-to-date data and keep the motor in working condition.
Diagnostics of a mechanical thermostat often requires its dismantling and testing the contacts with a tester. Electronic sensors are tested for resistance, which should vary depending on the ambient temperature. The faulty element must be replaced with a similar one, since there are no universal solutions here.
Refrigerant leak and problems with the defrost system
If the quantity in the circulation circuit has decreased freon, the refrigerator cannot reach the required temperature in the standard time. The compressor runs continuously, trying to compensate for the lack of refrigerant, but the cooling efficiency drops. Leakage can occur in places where pipes are soldered, in the evaporator, or due to corrosion.
Another reason is a malfunction of the system No Frost. If the defrost heating element, timer or defrost sensor fails, the evaporator becomes coated with ice. Ice blocks air circulation, and the temperature sensor in the chamber does not register cooling, forcing the motor to work continuously.
Signs of a leak or defrosting problems are often accompanied by additional symptoms:
- ❄️ Puddles or frost appear on the back wall of the chamber or on the floor under the refrigerator.
- 🔊 The compressor runs hotter than usual, vibration may be observed.
- 📉 Food in the main chamber spoils, although the freezer is still freezing.
- 💨 Warm or barely cool air blows from the vents.
To eliminate leaks require calling a technician with equipment to evacuate the system and refill with freon. It is impossible to independently eliminate the depressurization of the circuit without a special tool.
The influence of external factors and correct installation
The equipment can operate without interruption due to improper operating conditions. If the refrigerator is installed too close to a wall, heating appliances, or is in direct sunlight, heat transfer is disrupted. Condenser (black grille at the back) does not have time to give off heat, and operating efficiency decreases.
It is important to maintain clearances for ventilation. Air should circulate freely around the housing, especially in the condenser area. A condenser clogged with dust is also a common cause of overheating and continuous operation of the motor.
Compare the installation conditions of your refrigerator with the recommended parameters:
| Parameter | Normal | Consequences of violation |
|---|---|---|
| Gap at the wall | Minimum 5-10 cm | Condenser overheating |
| Room temperature | from +10 to +32 °C | Thermostat malfunction |
| Radiator cleanliness | Lack of dust | Reduced heat transfer |
| Chamber loading | No more 70% | Impaired air circulation |
Can a refrigerator be placed on a balcony?
A refrigerator can be operated on a glazed balcony only if the temperature there does not fall below the minimum permissible (usually +10°C) and does not rise above +32°C. Otherwise, the oil in the compressor will thicken or become too liquid, which will lead to breakdown.
Diagnostics and troubleshooting methods
If external factors are excluded, it is necessary to proceed to technical diagnostics. First of all, check if the Super Freeze (Super Freeze) mode is turned on. In this mode, the compressor operates continuously at the user's command. Disable this function and wait a few hours.
Next you should inspect the door and seal, as discussed above. If the seal is OK, listen to the sounds. Extraneous knocking or grinding noises may indicate mechanical wear on the compressor components. In this case, professional repair is required.
To check the thermostat yourself (in mechanical models), follow these steps:
- 🔌 Disconnect the refrigerator from the mains for safety.
- 🔧 Remove the temperature control knob and protective panel.
- 🔍 Remove the thermostat and visually inspect the contacts for carbon deposits.
- 📟 Test the contacts with a multimeter: at room temperature they should be closed.
☑️ Primary diagnostics of the refrigerator
When you need to call a specialist
There are a number of situations when self-repair is not only useless, but also dangerous. If you suspect a freon leak, a specific odor, or see oily stains on the tubes, further operation is prohibited. Professional soldering and refueling are required.
Also, do not try to disassemble the compressor itself. This is a sealed unit, and opening it at home will lead to permanent failure. If the engine hums but does not start, or makes clicking noises, the problem may be in the starting relay, the replacement of which is best left to a mechanic.
⚠️ Attention! Working with electrical circuits and refrigerants requires qualifications. A faulty start relay or a short circuit can cause a fire.
Contact the service center if:
- 🛠️ The compressor is hot, but no cold is produced.
- 🔌 When you turn on, you hear a click, but the motor is silent.
- 💧 A liquid or oil leak has been detected under the equipment.
- 🔥 There is a smell of burning or burning wiring.
Why does the refrigerator work continuously after defrosting?
If after defrosting the compressor does not turn off for more than 2-3 hours, this may be normal for the temperature to rise. However, if more time has passed, you may have damaged the sensor during cleaning, or there was air/moisture left in the system, or there was a power surge that damaged the thermostat.
Can an old refrigerator run without interruption?
Yes, older manual models often work longer than modern counterparts due to wear and tear on the seal and loss of insulation properties. However, continuous operation for more than 20 hours a day is also a sign of a malfunction for them.
What will happen if the malfunction is not eliminated?
Prolonged operation without stopping will lead to overheating of the motor windings, melting of the insulation and an interturn short circuit. As a result, the compressor will burn out, and replacing it will cost much more than timely repair of a small part.