The situation when the system refrigerator No Frost stops maintaining the temperature in the upper compartment causes panic among many owners, because this threatens food spoilage. Unlike classic models with a weeping evaporator, here cooling occurs due to the forced circulation of cold air, and disruption of this process requires immediate intervention.
Most often the problem lies not in a complete breakdown of the compressor, but in a malfunction of the air distribution system or freezing of the channels. Modern two-chamber units are designed so that cold is generated in the freezer and is supplied to the refrigeration compartment through special air ducts, so a malfunction of one element can paralyze the operation of the entire system.
Before calling a technician, it is worth conducting an initial diagnosis to understand the scale of the problem. If the compressor works continuously or, conversely, is silent, and there is heat inside, these are two different scenarios that require different approaches to the solution.
The principle of operation of the No Frost system and the distribution of cold
To understand why the upper chamber does not work, you need to understand the basic mechanics of the process. In units No Frost (which translates as “no frost”), the evaporator is hidden behind the back wall of the freezer. The fan drives air through the cooled fins of the evaporator and directs flows to both compartments.
Temperature control in the upper compartment is carried out automatically or manually using an air damper. If this mechanism is jammed in the closed position, cold air simply does not reach the products on the shelves, remaining below.
⚠️ Attention: An attempt to forcibly open the damper or blow through the channels without defrosting can lead to breakage of the plastic elements of the air duct system.
It is important to note that even with a working compressor, a violation tight seals or prolonged operation with the door open can disrupt the electronics operating algorithms, which will lead to failure of the upper level cooling.
It doesn’t freeze at all, but the light is on
The compressor hums constantly without stopping
You can hear clicks, but there is no cold
The upper chamber is warm, and the freezer is working normally-->
Faulty air damper and thermostat
One of the most common reasons why a refrigerator Indesit, LG or Samsung stops freezing from the top is failure of the air damper. This element is a valve that opens based on a signal from a temperature sensor, letting in cold air.
If the damper is stuck in the closed position, the upper chamber turns into a regular cabinet. You can check this by listening to the characteristic opening/closing sound when you turn on the device, although in some models this sound may be barely audible.
The problem may also lie in the thermostat or the temperature sensor located in the refrigerator compartment. If it transmits incorrect data that “seems to be cold,” the controller will not give a command to open the damper or start the fan.
- ❄️ Freezing of moisture in the damper mechanism blocks its movement.
- 🔌 Break in the electrical damper control circuit due to contact oxidation.
- 🌡️ Failure to calibrate the temperature sensor leads to incorrect readings.
Diagnostics of these components requires disassembling the internal panel of the refrigerator compartment. Often, condensation accumulates under the plastic, which, when frozen, disrupts the operation of electrical components.
Problems with the fan and evaporator blowing
Heart system No Frost is a fan that circulates air. If it stops rotating, cold air remains in the freezer area, not reaching the upper shelves of the refrigerator compartment.
The reason for the stop may be either a burnt-out motor winding or simple frosting of the blades. Ice freezes due to a violation of the defrost cycle, which will be discussed below. In this case, the fan simply cannot turn.
Sometimes the problem is mechanical in nature: a foreign object (a piece of ice, a product label) gets into the blades and blocks rotation. This is often accompanied by a characteristic hum or crackling sound from the rear wall.
You can check the operation of the fan by opening the door of the refrigerator compartment (in some models it should stop when the door is open, in others it should work constantly). If there is no operating sound when the door is closed, and the freezer is quiet, the fan is most likely faulty.
Failure of the defrost cycle and freezing of the channels
The most insidious reason why the upper chamber in refrigerators does not freeze Electrolux, Beko or Atlant is a violation defrost systems. In No Frost mode, the ice accumulating on the evaporator must be periodically melted by the heating element. If this process does not start, the channels become clogged with ice.
Air physically cannot pass through the ice plug to the top of the refrigerator. Visually, this can manifest itself in the form of a snowy “coat” behind the back panel of the freezer, which can be noticed during deep defrosting.
⚠️ Attention: If after complete defrosting (more than 24 hours) the refrigerator stops freezing again after 1-2 weeks, the problem is guaranteed to be in the defrosting system.
There are three main elements responsible for the defrosting cycle: Evaporator heating element, defrost sensor and timer (or electronic control module). Failure of any of them leads to ice fouling on the evaporator and cooling stops.
How to check a defrost heating element with a multimeter?
To check, you need to get to the heating element, remove the terminals from it and ring the tester in resistance measurement mode. A working heating element should show a resistance in the range from 200 to 500 Ohms. If the device shows “infinity” or one, the heating element has burned out and requires replacement.-->
Freon leakage and compressor malfunctions
Although in systems No Frost problems with air circulation are more common, technical malfunctions of the refrigeration circuit cannot be ruled out. If the refrigerant (freon) becomes low due to a micro-leak, there is not enough of it for the entire volume, and it is the upper chamber that stops freezing first.
In such cases, the compressor can work almost non-stop, trying to gain temperature, but to no avail. The evaporator in the freezer may be unevenly covered with ice or be completely warm.
Another option is a breakdown of the compressor itself. If it hums but does not start, or operates with strong vibration and clicking, the starting protection mechanism or motor windings may have failed.
Symptom
Probable cause
Nature of compressor operation
Heat at the top, cold below
Capillary clogged or freon leak
Works constantly or turns on frequently
Complete lack of cold
Compressor malfunction
Does not turn on or clicks
Uneven cold
Fan malfunction
Works normally
Ice crust behind the wall
Defrost failure
Works intermittently
Diagnostics of freon leaks at home is impossible without special equipment, since the gas is colorless and odorless. The technician looks for a leak using a leak detector or by characteristic oil stains on the tubes.
Electronic control module and sensors
Modern refrigerators, such as LG or Samsungare controlled by complex electronics. If the “brain” of the device receives distorted signals from the sensors or has a software failure, it may incorrectly control the cooling modes.
Often the cause is oxidation of the contacts on the board or the sensors themselves due to increased humidity inside the case. Water can flow there if the floor around the appliance is not defrosted or washed properly.
Many models are equipped with a self-diagnosis system. If there is a malfunction, error codes may light up on the display (for example, for a problem with a fan or for a defrost sensor). The decoding of the codes must be found in the instructions for the specific model. Er FF for a fan problem or Er ds for defrost sensor). The decoding of the codes must be found in the instructions for the specific model.
| Symptom | Probable cause | Nature of compressor operation |
|---|---|---|
| Heat at the top, cold below | Capillary clogged or freon leak | Works constantly or turns on frequently |
| Complete lack of cold | Compressor malfunction | Does not turn on or clicks |
| Uneven cold | Fan malfunction | Works normally |
| Ice crust behind the wall | Defrost failure | Works intermittently |
Er FF for a fan problem or Er ds for defrost sensor). The decoding of the codes must be found in the instructions for the specific model.