The device working principle and example of calculating power conditioner

By Admin | Garden And Buildings / Construction
27 April 2016

To understand the principle of the air conditioner does not have to be a graduate of a technical college on profiling specialty.It is enough to refresh the memory of the main points of the school physics course, to get some clarifications on issues of interest and then ... Then you can consciously choose the air-conditioning system, your choice will not affect the eloquence of a sales assistant, and, most likely, you will not be offended magic word "sale".For your decisions will be a serious basis - the necessary knowledge and understanding of what kind of device is needed in your case specifically.You will understand how to calculate the power of the unit and do the calculation yourself!Understanding how the air conditioning, to help prevent annoying errors during operation.You will be proud of a good buy!Let's get started ...


bit of theory for understandingEssentially processes ↑

How wonderful device called "air conditioning" is able to cool, and sometimes heat the air?- To answer need to remember only one rule from school physics course.As you remember, the evaporation of liquids (transition from liquid to gaseous state), the absorption of heat, ie. E. Cooling (remember how cold it becomes a cloth soaked in acetone).

In the reverse process - condensation (transition of a substance from a gaseous to liquid), heat is released, t. E. Heat that is also used in air conditioners.On this principle work not only air conditioning but almost all cooling devices (refrigerators, refrigerators, water coolers).The refrigerant in these units are commonly used CFCs, they possess the property at a relatively small pressure changes to pass easily from the gaseous fraction to liquid and vice versa.

main species aggregates ↑

To begin with a brief look at what all are air-conditioned and what the main differences between the different types of equipment.Depending on the application and purpose, there are many types and models of air conditioners: industrial, household, automotive, window, stationary and portable.

Industrial air conditioners are characterized by high power and energy, they are able to regulate the climate in large spaces, for household models more relevant parameters such as efficiency, quiet operation and easy maintenance.Air conditioners may be provided in a single housing, or consist of several parts, but a schematic diagram of the air conditioner based on any rule already discussed above.

The scheme is clearly illustrated by the example of the work of air conditioners split system
scheme, clearly illustrating the air conditioner as an example of a split system

today in everyday life are the most popular split-system (as the most productive, cost-effective and easy to use), so let's look at an example of such a device the features of air conditioners.

The unit air conditioner as an example of a split system ↑

Despite the fact that the split-system consists of indoor and outdoor units, on the basis of the work she repeats device domestic air-conditioner of any other type, because it is based is fully sealed closed loopfilled with a refrigerant consisting of copper tubing connected heat exchangers.The heat exchanger in the indoor unit is called an evaporator, and in the outer - capacitor.

refrigerant flowing through the system transfers heat between the heat exchangers, all this is due to the compressor in an external unit.For efficient heat exchange between the refrigerant and air in each of the blocks set fan drives air through heat exchangers.Another important node device is the throttle device, it is installed in the indoor unit before the evaporator and the need to reduce the pressure refrigerant to convert the latter into a gaseous fraction.

The outdoor unit of a split system unit cools the refrigerant
in the outdoor unit of a split system unit cools the refrigerant

whole process of the air conditioner in the cooling mode, the air is as follows.The compressor in the outdoor unit pumps the refrigerant, increasing the pressure in the condenser heat exchanger than it causes a transition to the liquid fraction, which is accompanied by evolution of heat which is removed into the air through the fan.

The cooled refrigerant is fed via copper piping to the indoor unit, which passes through the throttling device, boils, turning into a gaseous state, absorbing heat, evaporation cools the heat exchanger.The indoor fan blows air taken from the room, which is cooled, is returned.At the same time on the plates of the evaporator is condensed moisture, which is given to plastic tube to drain or outside.Then the refrigerant returns through the copper pipe to the compressor and the cycle repeats.

In the indoor unit of a split system air is cleaned
the indoor unit of a split system is made air cleaning and cooling (and heating, if provided design)

Some air conditioners can operate in heating the air in the room for this in the outdoor unit of a split system has a four-wayvalve through which the refrigerant movement in the opposite direction.In this case, the condenser becomes the evaporator, condenser and evaporator.

How to calculate the required power ↑

Since most air conditioners are used to cool the air, and less for heating, the calculation is made on the air conditioning cooling capacity.An important point - not to be confused with a cooling capacity of the air conditioning power consumption.Cooling capacity from household air conditioners in 2.5-4 times higher than the power consumption of their electricity.It turns out that the efficiency of the device at 300%!How is this possible?It's pretty simple - electricity is used, in fact, not cooling the air, but only on the transfer of heat from indoors to outdoors.

approximate calculation of the air conditioner area is made based on the ratio - 1 kW of cooling capacity to 10 m2 of floor space with a ceiling height of 3 m. For a more accurate calculation should take into account the heat emitted by electrical appliances, people staying in the room, window size and intensity of exposure to the sun.When the location of the room on the south side and a large area of ​​windows required power reserve up to 20%.

formula for calculating the capacity of the air conditioner is as follows:

Q = S * h * q, where

Q - tributaries of heat (W);

S - room area (m2)

h - height of the room (m);

q - coefficient of sun exposure (strongly lighted 40 W / m3, medium - 35 W / m 3, slightly - 30 W / m 3).

These inflows should be added to 0.1 kW of heat for each person, and about 1/3 of the nameplate capacity of working in the electrical room.

summing all heat gains may be necessary to know the calculated cooling capacity of the air conditioner.

It is important to calculate the performance of the air conditioner.It is clear that in the heat with a lack of air conditioning capacity simply can not cope with the task will be to work wear and prematurely released from the system, but also extremely powerful device also should not take.Air high power in a small room will often be switched off, which, in fact, will contribute to premature wear.

well in terms of soft power distribution inverter air conditioners.The principle of operation of the inverter air conditioner is the ability to change the capacity of the compressor without completely turning it off.Non-stop operation of the compressor greatly reduces wear and saves energy and allows for more flexibility to adjust the room temperature.

That's all.This information will help to orient the purchase, because you know now how to calculate the power and air conditioning for the area to find out how its performance and what is the fundamental difference between inverter air conditioners.