The situation when the temperature rises in the refrigerator often takes you by surprise, threatening the safety of food. Owners of household appliances may notice that food begins to deteriorate faster than usual, frost disappears on the walls, and it becomes warm inside. This is an alarm signal indicating a malfunction of the cooling system or the tightness of the circuit.
The reasons for this behavior of the unit can vary from trivial operating errors to complex technical malfunctions of the compressor. Understanding the operating principles refrigeration circuit will help you quickly identify the source of the problem. In some cases, it is enough to simply defrost the chamber, in others, you will need to replace expensive components.
In this article we will look in detail at why the temperature rises in the refrigerator, and how to diagnose a breakdown without calling a technician. You will learn to distinguish software failures from physical damage. This knowledge will save you time and money when servicing equipment.
Primary diagnostics and external factors
Before sounding the alarm and looking for spare parts, it is necessary to exclude external factors. Often the reason that the temperature rises in the refrigerator lies not in a breakdown, but in operating conditions. Check that the unit is not standing close to a wall or heating appliances. Impaired air circulation around of the condenser leads to overheating and ineffective operation.
Pay attention to the tightness of the door. If sealing rubber band is worn out or dirty, warm air constantly enters the chamber. The compressor does not have time to cool the volume, and the temperature rises. Also check if the chamber is overloaded with food, blocking the flow of cold air.
⚠️ Attention: If you have just placed a large amount of warm food in the chamber, the temperature may have risen temporarily. Give the equipment time to get into operation.
It is important to assess how stable the voltage in the power supply network is. Voltage surges can lead to malfunctions electronic control module, which causes chaotic switching on and off of the compressor. In such cases, the equipment does not have time to gain cold.
Problems with the thermostat and temperature sensors
One of the most common reasons why the temperature in the refrigerator rises is failure thermostat. This element is responsible for turning the compressor on and off depending on the temperature in the chamber. If thermostat jammed in the "off" position, the motor will not work.
In modern models with the system No Frost electronic sensors are responsible for climate control. Their readings are read control module. If the sensor “lies” and shows that the chamber is colder than it actually is, the compressor simply will not start. Diagnostics of such elements requires a multi-MRT.
Signs of a thermostat malfunction are often accompanied by the absence of a click when turning the regulator knob. On electronic models, error codes may light up on the display. Replacing the sensor is a relatively simple procedure, but requires precision.
How to check a mechanical thermostat?
Unplug the refrigerator, remove the thermostat and immerse its sensitive tube in ice water. If after 2-3 minutes there is no click, the device is faulty.
It is worth noting that in two-compressor models, the failure of one thermostat affects only one chamber. If there is only one compressor, and damper the air supply is jammed, cold will not flow into the refrigerator compartment, although the temperature in the freezer may be normal.
Malfunctions of the defrosting system in No Frost models
In refrigerators with system No Frost the serviceability of the defrost system is critically important. If Evaporator heating element, the timer or thermal protection relay fails, a coat of ice builds up on the evaporator. The air stops circulating, and the temperature in the chamber rises.
Visually this can be manifested by the fact that cold air stops blowing from the air ducts. The compressor may work continuously, trying to cool the chamber, but to no avail. Ice blocks the operation fan, and the cold flow simply does not reach the products.
☑️ Diagnostics of the defrost system
A frequent problem is the heating element burns out. In this case, automatic defrosting does not occur and ice accumulates with each cycle. Eventually, the ice cocoon becomes so large that it completely blocks the channels.
⚠️ Attention: Trying to break off the ice with a knife or sharp objects can lead to breakdown of the evaporator and leakage of freon. Use only warm air for defrosting.
Refrigerant leakage and compressor problems
The most serious reason why the temperature in the refrigerator rises is a leak refrigerant (freon). Gas can escape through microcracks in the pipelines, often hidden in the foam layer of the casing. Without a sufficient amount of freon, the cooling cycle is disrupted.
Symptoms of a leak are often hot side walls (where normally they should be warm) or, conversely, a completely cold condenser. The compressor may work non-stop, but not produce cold. A quiet hissing or gurgling noise may also be heard.
Problems with the compressoritself, such as inter-turn shorting or piston wedge, also lead to loss of performance. The motor hums, but does not start, or starts for a couple of seconds and stalls due to thermal protection.
| Symptom | Possible cause | Probability of repair |
|---|---|---|
| The compressor hums and clicks | The starting relay or motor wedge is faulty | High |
| The refrigerator is silent, there is no light | Problem with the wiring or socket | Very high |
| The motor runs constantly, there is no cold | Freon leak or capillary clogged | Medium (requires vacuuming) |
| Temperature floating | The sensor or thermostat is faulty | High |
To eliminate the leak, it is necessary not only to seal the tube, but also to completely replace the filter-drier, evacuate the system and refill with new gas. This is a complex procedure that requires special tools.
Clogged capillary tube
Another technical reason why the temperature rises in the refrigerator is blockage capillary tube. This is a thin copper pipe that carries the refrigerant to the evaporator. A blockage can form due to moisture entering the system or oil oxidation products.
If a blockage occurs, the circulation of freon is disrupted. The compressor tries to pump gas, creating high pressure at the outlet and vacuum at the inlet. A characteristic sign is the heating of the compressor housing to very high temperatures and the absence of cold in the chambers.
Sometimes “pushing” the system with nitrogen under high pressure helps, but often a section of the capillary tube needs to be replaced. This operation is complicated and is performed only in service centers.
Failures in the electronic control module
In modern refrigerators, electronic moduleis responsible for all processes. Voltage surges, moisture or manufacturing defects can lead to failure of board elements. In this case, the “brains” of the refrigerator may incorrectly read data from the sensors or may not issue a command to start the compressor.
Often the module requires flashing or replacing burnt-out radio components. Repairing a board yourself is only possible if you have deep knowledge of electronics and soldering. In most cases, the entire module is replaced.
Symptoms can vary: from complete failure of the equipment to chaotic activation of light indications and sound signals. If the temperature in the refrigerator rises and all mechanical components are working properly, it is worth checking the voltage at the output of the module.
⚠️ Attention: Technical characteristics and location of elements may vary depending on the brand and year of manufacture. Always check the official diagram of your model before starting work.
Frequently asked questions and answers (FAQ)
Why does the temperature rise in the refrigerator after defrosting?
If after defrosting the temperature does not drop for a long time, you may have closed the door too early, not allowing the system to return to normal. The compressor operating cycle could also be disrupted. Wait 2-3 hours. If the cold does not appear, check whether the temperature sensor is flooded with water.
Can the temperature rise due to the heat in the room?
Yes, if the room is hotter than +30°C, the refrigerator may not cope, especially if it is old or the condenser is clogged with dust. In such conditions, heat exchange is broken, and the equipment works at its limit.
What to do if the temperature rises in only one chamber?
In two-compressor models, this indicates a problem in the circuit of a particular chamber (thermostat, leak). In single-compressor units, most likely there is a problem with the air supply damper or the fan. No Frost.
How long does the refrigerator keep the temperature when the lights are turned off?
A working modern refrigerator keeps the cold from 8 to 24 hours, if you do not open the door. Older models may lose temperature in 3-5 hours. The presence of a system No Frost usually improves thermal insulation.