The device and principle of operation of the air conditioner fan

The fan is an important element of household, automotive and industrial air conditioners. The operation of this device provides cooling of the condenser, inside of which at a certain stage of circulation the refrigerant is converted from a gaseous substance into a liquid. The heat generated in this case is forcibly removed from the premises. If the fan malfunctions, the condenser may overheat, which will lead to a malfunction of the entire system.

Split system device

How should a household air conditioning fan work?

In a simplified form, the design of the fan is an impeller mounted on an electric motor shaft, which drives it into rotation. Depending on the installation location and the function performed, the shape of the blades and features of the work may vary.

Given that the vast majority of domestic air conditioners for residential premises are a split system consisting of an indoor and outdoor unit, its operation scheme provides for a fan in each of the units.

Device and Functions of Indoor Fan

The principle of operation of all air conditioning systems is based on the physical properties of the liquid to collect heat during evaporation and to give off heat during condensation. In split systems, refrigerant is used as a coolant - freon, which boils and evaporates at room temperature. The indoor unit contains a special device - an evaporator. Passing through it, the warm air from the room cools down and returns back in the form of cold air. Another important element of the indoor unit of the air conditioner is the fan, which provides forced circulation through the heat exchanger.

Indoor fan

The diagonal fan of the indoor unit has the form of a hollow cylinder, on the walls of which there are impeller elements. The evaporator, as it were, goes around it, providing for the intake of warm air from the front and upper sides of the unit. Cooled air passing through the fan and diffuser is fed back into the room. The controls inside the unit provide turning on and off the electric motor, as well as changing the speed of its rotation.

Important! Diagonal models are quite reliable devices with compact dimensions and low noise level, but their main drawback is the inability to overcome significant obstacles to air flow, for example, when the filter is clogged.

Device and functions of outdoor fan

If the indoor unit serves to evaporate the refrigerant, then the reverse process takes place in the outdoor unit - the freon condenses, and the heat generated in this process is removed to the atmosphere. For this, the air conditioner is equipped with a special device - a compressor, which creates the high pressure necessary for a quick transition of gas into a liquid state. The condensation process is carried out in a heat exchanger having the form of a radiator, and is accompanied by heat generation. The fan of the outdoor unit has a standard shape with large blades, thanks to which it is possible to quickly remove heat to the outside and protect all elements of the unit, including the compressor, from overheating.

Outdoor fan

The principle of operation of the fan of the air conditioner

The development of technology has led to the emergence of air conditioning devices that provide a comfortable temperature in the room and even in the passenger compartment. The car air conditioner is capable of cooling or heating air flows and has a number of other useful functions:

• Maintains the set air temperature in the confined space of the car;
• Protects the interior of the cabin from dirt and dust from the outside;
• Prevents condensation on the windows in wet weather.

Auto air conditioning circuit

The principle of operation of an automobile air conditioner is similar to a household one, but differs in more compact dimensions. The high-pressure compressor compresses the freon and directs it to the condenser, where its temperature decreases. The inverse function is performed by the evaporator, where freon from a liquid state passes into a gaseous state. The car air conditioner uses only one fan, which cools the evaporator with a powerful stream of air at the same time as the condenser. It is driven by the engine, and its speed can be set manually or automatically using sensors. Thanks to this, it will not be hot inside the car, even if the car is stationary.

Possible causes of fan malfunction

If even the smallest malfunctions of the fan are detected, immediate measures must be taken to detect and eliminate the malfunction.

Important! If the device does not perform the functions assigned to it, this can lead to overheating of individual parts and assemblies, which can cause a more significant breakdown in the system.

In some cases, diagnostics cannot be performed without special knowledge and tools, but it is often possible to detect a malfunction on their own without the help of a specialist. Most often, a fan breakdown is caused by one of several reasons:

1. Lack of voltage on the contacts of the electric motor. Such a problem is detected in the event of a wiring failure or failure of individual parts of the electrical circuit.
2. The fixing screw on the turbine has been loosened or loosened, with which it is mounted on the motor shaft.
3. Worn or damaged bearings. This problem may occur if the air conditioner is not transported correctly or after many years of use.
4. Faulty electric motor. It is usually caused by a breakdown of insulation or a violation of the integrity of the motor winding, which simply does not turn on when voltage is applied.
5. Freezing of the blades. If the air conditioner is not equipped with a “winter” mode, then when you try to turn it on at a negative air temperature, the blades of the outdoor unit can be blocked by ice that is frozen inside. Therefore, it is strictly forbidden to use air conditioning in winter to heat the room.
   

   Freezing outdoor unit

6. Blade Lock This problem is typical for an external unit, inside of which branches or debris can get from the street, preventing the fan blades from spinning.