Modern refrigerators are radically different from the models our grandmothers used, especially with regard to cold distribution. Many users mistakenly believe that the same unit that compresses the refrigerant is responsible for air circulation inside the chamber, but this is not entirely true. In fact, compressor for blowing is a technically incorrect, but common in everyday life, name for a powerful fan that provides forced convection.
It is this element that forces cold air to move along given trajectories, preventing it from stagnating in one corner of the chamber. Without the forced movement of air masses, it would be impossible to implement the technology No Frostwhich has become the de facto standard for most modern devices.
In this article we will examine in detail why this mechanism is critical for maintaining the freshness of products, how it interacts with the main cooling circuit and what happens when it ceases to perform its functions. Understanding these processes will help you operate equipment correctly and quickly diagnose breakdowns.
The principle of operation of a forced air circulation system
To understand the essence of the process, it is necessary to clearly distinguish between two circuits: refrigerant and air. The first uses a classic piston or inverter compressor, driving freon through the tubes. In the second, a blower fan operates, which is often called a “blowing compressor” because of the flow pressure it creates.
Air from the refrigerator or freezer chamber is sucked in through special technological openings and passes through evaporator. There it cools, giving up its heat to the refrigerant, and with the help of a powerful flow it returns back to the chamber. This creates a uniform cooling effect throughout the entire volume.
This scheme avoids the formation of “warm zones” where products could quickly deteriorate. Unlike static cooling, where the cold simply falls down, active mixing of the masses occurs here.
The intensity of this process is regulated by electronics, which reads the readings of temperature sensors. If the temperature in the chamber has reached the set value, air compressor can be temporarily stopped to save energy, even if the main unit continues to operate.
Key tasks of the fan in No Frost refrigerators
The main function of the device is to ensure constant air exchange. However, this is far from the only problem that this unit solves in the complex life support system of the refrigerator.
Firstly, it is thanks to forced airflow that a rapid restoration of the temperature regime is achieved after opening the door. When you take a product, warm air gets inside, and a powerful flow instantly displaces it, driving it through the cooler.
Secondly, the system prevents the formation of an ice crust on the products and the walls of the chamber. The moisture released by the products does not have time to condense on the shelves, as it is constantly carried away by the flow to the evaporator zone, where it freezes out in the form of frost, which is then removed in the defrosting cycle.
⚠️ Attention: If you notice that the products in the depths of the chamber have become warm, but on the back wall, on the contrary, everything is frozen, this is a sure sign of a violation of air circulation, and not necessarily breakdown of the main compressor.
It is also worth noting the role of uniform distribution of cold for different types of products. Meat stored on the bottom shelf and milk on the top door receive the same amount of cold thanks to the competent aerodynamics of the flows.
Differences between a compressor and a blower fan
Frequent confusion in terms arises due to the fact that both devices create pressure and noise. However, their design and purpose are fundamentally different, and replacing one with another is impossible.
The main compressor is a sealed pump that operates with gaseous refrigerant under high pressure. It requires oil to lubricate rubbing parts and generates significant vibration. While the blower fan is an electric motor with an impeller that operates directly in the air environment of the chamber.
The technical characteristics of these units are also incomparable. The compressor consumes hundreds of watts of energy, while the blower motor consumes only 10-20 watts. Their service life also varies: the pump is designed for decades of operation intermittently, and the fan may fail earlier due to freezing or the ingress of foreign objects.
Here are the main differences in the form of a table for a visual comparison:
| Parameter | Main compressor | Blower fan |
|---|---|---|
| Working fluid | Freon (gas) | Air |
| Location | Rear, bottom (hermoblock) | Inside the chamber or behind the back wall |
| Noise level | Humming, vibration | Whistling, crackling, wind rumble |
| Repair | Only replacement by specialists | Do-it-yourself replacement is often available |
Understanding this difference is critically important when diagnosing. If the refrigerator hums, but does not cool, the problem is in one unit. If it is weakly cold and makes a “windy” noise, the problem is different.
In addition, control system it is independent of these elements. The electronic module can turn on the main circuit, but block the start of the fan if the sensor detects icing of the impeller.
Design features and location of the unit
Depending on the model of the refrigerator, be it Indesit, LG or Bosch, fan location may vary. Most often, it is hidden behind a decorative panel on the back wall of the freezer.
In dual-circuit systems (Full No Frost), there can be two such fans: one for the freezer, the second for the refrigerator compartment. They have different performance, since different volumes of pumped air are required for different temperature zones.
The fan impeller is made of frost-resistant plastic, which does not lose elasticity at extremely low temperatures. The motor axis often has special seals that prevent moisture from entering the windings.
Why can a fan jam?
Often the cause of the stop is ice formed due to a malfunction of the defrost heating element. The ice plug blocks the blades, and the motor burns out from overload or simply stops.
The motor is usually mounted on rubber dampers that dampen vibration. Over time, the rubber may harden, which will lead to a characteristic rattling sound during operation.
Access to the unit for maintenance most often requires partial disassembly of the inside of the chamber. It is necessary to carefully remove the shelves and protective screens so as not to damage the fragile plastic at low temperatures.
Typical symptoms of malfunctions of the blower system
Diagnosing problems with air circulation does not always require sophisticated equipment. Often the signs of breakdown are obvious even to a non-specialist, if you know what to look for.
The very first symptom is uneven cooling. Products near the back wall may become frosted, while milk on the door remains warm. This indicates that air circulation air circulation is impaired.
The second sign is a change in the nature of the noise. A working fan emits a uniform, quiet hum. If you hear a grinding, crackling or whistling sound, this may mean:
- ❄️ Ice on the impeller blades
- 🔧 Wear of the engine plain bearings
- 🧊 Freezing of the rotation axis
- 🔌 Problems with the electrical power circuit
It is also worth paying attention to the operation of the main compressor. If the fan does not work, heat exchange is disrupted and the main unit is forced to work without interruption, trying to gain temperature. This leads to its overheating and increased energy consumption.
Diagnostics and methods for troubleshooting
If you suspect a fan problem, the first step should be a visual inspection and checking for obstructions. Often pieces of packaging or labels get into the air ducts, blocking the flow.
To check the electrical part, you need to ring the motor windings with a multimeter. Lack of resistance will indicate an open circuit, and too low resistance will indicate an interturn short circuit. In both cases, replacement of the unit is required.
It is also important to check the defrost system. If the heating element does not heat up or the timer does not give a signal to defrost, the evaporator becomes overgrown with ice, which mechanically stops the fan. In this case, replacing the fan itself will not solve the problem for a long time.
☑️ Procedure for checking
During assembly, it is important to correctly install the seals and screens. The slightest leak will lead to the suction of warm air and rapid re-icing of the system.
⚠️ Attention: Before starting any work inside the chamber, be sure to defrost the refrigerator for 24 hours. An attempt to remove plastic elements in the cold will lead to their destruction.
If you are not confident in your abilities, it is better to contact a specialist, since incorrect assembly can disrupt the aerodynamics of the flow, and the cold will again begin to be distributed unevenly.
Operation rules to extend service life
In order compressor for blowing and the entire No Frost system to serve for a long time, you must follow the rules for loading cameras. Do not block the air outlets with food.
Regular defrosting, even for No Frost systems, is useful. Once every year or two, it is recommended to completely turn off the device for a day to allow hard-to-reach places where moisture and mold can accumulate to dry.
Monitor the condition of the door seals. If they allow warm air to pass through, the fan system works harder to compensate for the heat gain, which leads to accelerated wear of the fan bearings.
Use the correct packaging. Open containers with liquids increase the humidity in the chamber, which also accelerates the process of ice fouling on the elements of the circulation system.
Why does the fan hum only after defrosting?
If a humming noise appears immediately after switching on, there may be ice left on the blades that has not yet melted, or the grease in the bearings has thickened in the cold. After 10-15 minutes of operation, the noise should disappear. If not, the bearing is worn out.
Is it possible to operate a refrigerator with a non-working fan?
Short-term - yes, but the food will deteriorate unevenly. Long work without blowing will lead to overheating of the main compressor and eventual failure, since heat will not be effectively removed from the evaporator.
How often should the fan be changed?
The service life of a high-quality fan is 10-15 years. However, in conditions of hard water (scale formation on heating elements) and power surges, it may require replacement after 5-7 years of operation.
Does the type of refrigerant affect the operation of the fan?
No, the type of freon (R600a or R134a) affects only the operation of the main compressor and heat exchange. The fan works with air, and its characteristics depend only on the design of the impeller and the power of the motor.