The refrigerator stopped turning off: reasons and solutions

The situation when the refrigerator has stopped turning offis one of the most alarming for the owner of household appliances. The continuous hum of the engine not only irritates the ear, but also indicates that the unit is working hard, trying to achieve the set temperature parameters, but cannot do so. In normal operation, the compressor should turn on and off at certain intervals, maintaining the cold inside the chambers.

If you notice that refrigerator it is humming for days on end, and the temperature inside remains not low enough or, conversely, food begins to freeze, you cannot ignore this. Long-term work without rest leads to overheating compressor, melting of the wiring and, ultimately, to expensive repairs or complete replacement of the unit. It is important to quickly diagnose whether the problem is a consequence of improper operation or a technical malfunction.

In this article we will look in detail at the main reasons why The refrigerator does not turn off, and consider what steps you can take yourself, and when it is better to call a technician. Understanding the principles of operation of the cooling system will help you save time and money.

Failure of the door seal

The most common and easily eliminated reason for the continuous operation of the refrigerator is the loss of the seal of the chamber. If sealing rubber the door is worn out, cracked or dirty, warm air from the room constantly enters the chamber. Sensors detect an increase in temperature and command the compressor to work without interruption to compensate for the heat gain.

Often the problem lies not in the rubber itself, but in the misalignment of the door. If refrigerator is not level or has been subjected to mechanical stress, the door may not fit tightly. In this case, the cooling system simply does not have time to cool the volume of the chamber to the required values, since the cold constantly “escaps” outside.

⚠️ Attention: Even a microscopic gap in the seal can increase the energy consumption of equipment by 20-30% and lead to compressor failure due to overload.

To check the tightness, 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 and without resistance, it means that in this place seal does not perform its function.

• 🧼 Clean the rubber circuit from grease and adhered dirt with warm water and soap.
• 🔥 Gently warm up deformed areas of the seal with a hairdryer and straighten them.
• 🔧 Adjust the position of the door using the fastening hinges if it is skewed.
• 🛒 Replace the sealing rubber with a new one if it has lost elasticity or is torn.

If after these manipulations the refrigerator continues work without stopping, the problem most likely lies deeper, in the electronic or mechanical components of the system.

Malfunctions of the thermostat and temperature sensors

The thermostat (thermostat) is the “brain” that decides when to turn the compressor on or off. If thermostat fails and is “stuck” in the “on” position, it will constantly send a signal to the motor to cool, even when the desired temperature has already been reached inside. In mechanical models, this is a common problem due to contact wear or loss of bellows sensitivity.

In modern models with a system No Frost and electronic control, the role of a thermostat is performed by air sensors. If such a sensor is contaminated with frost, is displaced from its place, or has an open circuit, it transmits incorrect data about the temperature in the chamber to the control module. The control unit, receiving a signal that it is “heat,” does not give a command to turn off.

Diagnostics of electronic sensors requires the use of a multimeter to measure resistance. A discrepancy between the readings and the actual temperature values indicates the need to replace the element.

Replacement thermostat or sensor - a procedure available to a home craftsman, but requiring precision. It is important to install an element with similar characteristics, otherwise the operating modes will be disrupted.

Refrigerant leak and problems with the compressor

If the refrigerator is humming, but does not cool (or cools very weakly), and at the same time does not turns off, there is a high probability of freon leakage. The refrigerant circulates through the system, picking up heat. When its quantity decreases due to microcracks in the tubes or corrosion, cooling efficiency decreases. The compressor tries to compensate for the lack of freon by operating in continuous mode.

The other extreme is a malfunction of the compressor itself. Wear of the piston group or valves leads to the fact that the motor cannot create the necessary pressure in the system. It runs "idle", consuming electricity but not cooling the camera. This can be determined by the characteristic sound: instead of a confident hum, you can hear a quiet buzz or clicks.

Freon leakage is not just a technical problem, but also a safety issue. Although modern refrigerants are less toxic, inhaling them in high concentrations is harmful. In addition, operating a compressor without sufficient oil (which circulates along with freon) can quickly damage it.

• 👀 Visually inspect the tubes at the back of the refrigerator for oily stains (freon carries away oil).
• 👂 Listen to the sound of operation: hissing may indicate gas escaping.
• 🌡️ Check the temperature of the condenser (grid at the back): it should be warm evenly.
• ❄️ Pay attention to the presence of frost in only one corner of the freezer (a sign of a lack of freon).

To eliminate a leak, you need to call a technician with special equipment to find the place of damage, solder and refill system refrigerant.

Clogging of the capillary tube and filter-drier

In the refrigerant circulation system, the capillary tube and filter-drier play an important role. Over time, oil oxidation products may form in the system or moisture may enter the system, which leads to the formation of an ice plug or blockage. If capillary tube is clogged, freon cannot circulate normally.

When clogged, the compressor begins to pump freon in one direction, creating excess pressure in front of the plug and vacuum after it. This causes a characteristic sound: the motor runs, then a click is heard (the protection is triggered or the pressure drops), and it starts again, or it works continuously, trying to push through the plug. No cooling occurs.

⚠️ Attention: Trying to clean the system yourself without a vacuum pump and professional tools can lead to complete failure of the compressor.

Symptoms of a blockage are often confused with a freon leak, since the external manifestations are similar: refrigerator does not freeze and does not turn off. However, if clogged, the filter drier may be hot, and the tubes next to it may be cold or covered with frost.

The solution to the problem is to purge the system with nitrogen under high pressure, replace the filter-drier and refill Freon. This work should only be performed by a qualified specialist.

Failures in the defrost system (for No Frost models)

In refrigerators with a No Frost system, continuous operation of the compressor is often associated with a malfunction of the evaporator defrost system. If the defrost heating element, timer or defrost sensor fails, a “coat” of ice builds up on the evaporator. This ice blocks the circulation of cold air through the chamber.

• 🔌 Defrost the refrigerator completely (at least 24 hours with the doors open).
• 🌬️ If after defrosting the refrigerator worked normally for a while, the problem is in the defrosting system.
• 🛠️ Check the evaporator heating element circuit for a break.
• ⏱️ Test the defrost timer (in mechanical models) or the control board.