A sudden change in temperature in the refrigerator compartment is always a signal of a malfunction of the equipment. You open the door to get the milk only to find a crust of ice on the food that should be kept fresh and chilled. This situation not only spoils the food, but also indicates that the control system has stopped reading data or executing commands correctly.
If your unit begins to operate in the “super-freeze” mode without your participation, this cannot be ignored. Freezing often precedes more serious compressor breakdowns or electronic failure. In most cases, the problem lies in a violation of the circulation of the refrigerant or incorrect operation of the sensors responsible for stopping the motor.
Before calling a technician, it is worth conducting independent diagnostics to eliminate common operating errors. Often the cause is an incorrectly set mode or a simple sticking of the seal. Understanding the principles of operation compressor group will help you quickly identify the source of the malfunction and save on repairs.
Checking temperature settings and functions
The most common and easily eliminated reason is accidental activation of the intensive freezing function. On modern models, such as LG or Samsung, this option may turn on when you accidentally touch the touchpad or stick buttons. In this mode, the compressor operates continuously, ignoring standard rest cycles.
Check the control panel and make sure that the Super Freeze or “Freeze” indicator is not lit. If the function is activated, turn it off and wait a few hours until the temperature stabilizes. In models with mechanical control, it is necessary to check the position of the regulator - perhaps it has been shifted to the “Maximum” position.
⚠️ Attention: Long-term operation in super freezing mode (more than 24 hours) can lead to freezing of the evaporator and subsequent breakdown of the compressor due to overload.
It is also worth paying attention to the settings in the digital menu if your model is equipped with a display. Sometimes after power surges or a power failure electronic module it can reset the settings to factory settings or go into emergency mode.
Malfunctions of the thermostat and thermostat
The thermostat (or thermostat) is the “brain” that decides when to turn on or turn off the compressor. If the refrigerator begins to freeze too much, there is a high probability that the contacts inside the thermostat are “stuck” in the “on” position. In this case, the motor does not receive a signal to stop and drives the cold until the thermal protection relay operates.
Diagnostics of a mechanical thermostat requires caution. It is necessary to remove the regulator and check its contacts with a multimeter. If the rod does not open the circuit when the temperature changes, the part must be replaced. In modern models with the system No Frost this function is performed by air temperature sensors, which can also give incorrect readings.
- 🔍 Symptoms of failure: the compressor operates without interruption, the products in the upper part of the chamber are covered with frost.
- 🛠️ Check method: short-term shutdown of the device from the mains (for 15-20 minutes) sometimes helps to “unfreeze” stuck contacts.
- 💡 Nuance: in two-compressor models, thermostats are separate for the refrigerator and freezer compartments.
Replacement thermostat - the procedure is not complicated, but requires precision. It is important to choose an analogue with identical parameters, otherwise the temperature regime will be disrupted. For models Indesit i Atlant universal thermostats of the TAM series are often used.
How to check the thermostat without instruments?
Immerse the sensitive tube of the thermostat in water with ice. If after 2-3 minutes you do not hear a click of the contacts opening, the part is faulty.
Problems with the temperature sensor and electronic module
In electronically controlled refrigerators, thermistors are responsible for temperature control. These are semiconductor elements whose resistance changes depending on heating or cooling. If temperature sensor fails and transmits a false signal to the control module that there is “heat” in the chamber, the compressor will operate continuously.
Often the problem lies not in the sensor itself, but in oxidation of the contacts or broken wiring leading to it. Moisture that gets inside the camera may cause corrosion of the connectors. In such cases, the control module receives an intermittent signal and goes into emergency mode of continuous operation.
| Fault type | Probability | Difficulty of repair | Symptoms |
|---|---|---|---|
| Open sensor circuit | High | Medium | Display error |
| Module software failure | Medium | High | Chaotic operation |
| Oxidation of contacts | High | Low | Periodic failures |
| Incorrect calibration | Low | Low | Constant under/overshoot |
Diagnostics of the electronic module often requires special equipment. However, in some cases, a full reset helps. The procedure is performed differently for each brand: for Bosch this is a long press of the button, for Haier a key combination.
Faults No Frost systems and switching valve
In systems No Frost a special valve (throttle valve) is responsible for the distribution of cold. It directs cold air into either the freezer or refrigerator compartment. If the mechanism is clogged with ice or jammed in the open position, cold air from the freezer will constantly blow into the refrigerator compartment.
The result is the rapid accumulation of frost on the food at the back wall. Products lying close to the duct freeze first. This is a classic situation when the refrigerator “freezes,” although the compressor can turn off in time.
- ❄️ Cause: malfunction of the damper motor or ice freezing on its mechanism.
- 🌬️ Symptom: strong flow of cold air from the hole in the back wall.
- 🔧 Solution: complete defrosting of the unit within 24 hours or replacing the damper motor.
It is also worth checking the condition of the evaporator. If the defrost system (heating element, timer, defrost sensor) does not work correctly, a “fur coat” grows on the evaporator. The fan begins to drive this cold air into the chamber, which leads to a sharp drop in temperature.
⚠️ Attention: Trying to forcibly open a frozen damper can lead to breakage of the plastic motor gears. Preliminary defrosting is required.
Freon leakage and compressor operation
Paradoxically, a refrigerant (freon) leak can also lead to freezing, but under specific conditions. When there is little gas left in the system, the compressor tries to compensate for the lack of cold by working hard. At a certain point, due to changes in pressure and boiling point of the refrigerant, the evaporator may become covered with an ice crust (“snow coat”), which then begins to melt and freeze elsewhere.
However, more often, when there is a leak, the opposite effect is observed - the refrigerator stops freezing. But if you see that the freezer is working normally, but everything in the refrigerator compartment is frozen, and the compressor is hot and running non-stop, this may be a sign incomplete cycle or problems with the capillary tube.
Clogged capillary tube or filter drier disrupts the circulation of freon. The pressure in the system increases, the compressor hums, and the temperature fluctuates. Local hypothermia may be observed at some points in the system.
The influence of seals and operating conditions
The reason does not always lie in "iron". Worn or dirty door seal allows warm, moist air inside. The compressor reacts to the increase in temperature and begins to work more intensely. Moisture from the air condenses and freezes on food and walls, creating the illusion that the refrigerator is freezing too much.
Check the tightness of the rubber around the entire perimeter. Use a simple test with a piece of paper: hold it in the door and try to pull it out. If the sheet comes out freely without resistance, the seal is broken. The reason may also be door misalignment due to worn hinges.
It is important to take into account external factors:
- 🌡️ Temperature in indoors: if the room is too cold (below +10°C) or hot (above +30°C), the refrigerator may not work correctly.
- 🍲 Hot foods: Inserting warm dishes forces the unit to work at its limit.
- 🧊 Loading density: A refrigerator that is too full disrupts air circulation, creating zones of local hypothermia.
☑️ Diagnosis of the seal
Frequently asked questions and answers (FAQ)
Why do food freeze only at the back wall of the refrigerator?
This is a normal phenomenon for a drip defrosting system if the temperature is not lower than 0°C. If ice forms, it means that the air circulation is disrupted or the thermostat setting is too low. Move the food away from the wall by 2-3 cm.
Can a refrigerator freeze due to a power surge?
Yes, a power surge could damage the electronic control module or the start-up relay might be stuck. In this case, the equipment requires professional diagnostics of the electrical circuit.
What to do if after defrosting the situation repeats?
If 24-hour defrosting did not help, the problem is of a technical nature. Most likely, the thermostat, sensor or damper motor has failed. The faulty part needs to be replaced.
Is it dangerous to operate a refrigerator that freezes?
Yes, it is dangerous. Constant operation of the compressor without rest cycles leads to overheating and burnout of the windings. In addition, ice can damage plastic parts and products.