How to calculate air conditioning?

Buying an air conditioner is not an easy task. It is necessary to determine the functional, design and brand, and still need to know how to calculate the air conditioner, so that its performance corresponds to the volume of the room. From the last parameter depends not only the cooling efficiency, but also the operating life of the unit. After reading this article, you will be able to calculate the split system in the most accessible way for you.

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How to calculate the air conditioner?- Three available ways of

Actually, there are few ways of calculating the cooling capacity of the air conditioner:

• With the use of special online calculators - they are placed on the portals of manufacturers and dealers who are engaged in selling household appliances.
• By the criterion of the area of ​​the room.
• Calculate the air conditioner by formulas that take into account the room volume and the thermal sources in it.

Important! There is also a special thermophysical calculation, but it is quite complicated for the uninitiated user. As a rule, this technique is used for calculations by design engineers.

Using the online calculator

The essence of this method is as follows. On-line portal of manufacturers of home appliances there are online calculators. Using them, you greatly simplify the procedure for calculating the cooling capacity of the unit.

You just need to fill in the required fields:

• room parameters;
• desired air temperature;
• number of radiators.

Then, by clicking the calculation button, you get the desired wattage figure, which can be safely taken as a basis. This is a fairly simple and quick method. However, he has a significant drawback - universality. We have no idea what heat supplies from different sources are in the program. Sometimes the value of power is obtained with a large "margin", and this - additional cash costs. For this reason, it is desirable to check the figure obtained by calculations using other methods.

Calculation of the area of ​​the room

This technique is often used by sales representatives. How to calculate the air conditioner by this method? The essence of it is as follows. This is based on the following statement: with a ceiling height of 3.0 m, 100 W of cold power should be allocated per square foot of the living space.

Important! For example, if the area of ​​the room is 20 "squares", then the desired wattage is 2000 W.

With a higher ceiling height, the specific cooling capacity is selected in accordance with the table:

• 3,0-3,4 m - 0,120 kW / square meter.
• 3,4-4,0 m - 0,140 kW / square meter.
• More than 4.0 m - 0.160 kW / square meter.

A more precise calculation is obtained if we take into account the power reserve used to compensate heat receipts from people in the room and from household appliances. It is accepted to use the following conditional values ​​of the released amount of heat( in terms of wattage):

• Person - 0.3 kW.
• The unit of household appliances - 0,3 kW.

Important! For example, if a person who works on a computer is permanently in the room, then 600 more should be added to the results obtained in the calculation of 2000 W. As a result, we get 2600 Watts.

If you calculate the air conditioner in this way, we get overvalued figures. The amount of heat released by a person is:

• at rest - 0.1 kW;
• at low load - 0,13 kW;
• when performing heavy work - 0.2 kW.

Calculation of refrigeration capacity according to the room cubicle

This calculation is based on the value of the specific amount of cold per cubic meter of room volume. The calculation is especially accurate if the squaring of the room does not exceed 70. Let us denote the specific power factor through q.

Its value is accepted:

• for shaded areas - 30 W / cubic meter;
• for premises with medium illumination - 35 W / cubic meter;
• for premises located on the sunny side - 40 W / cubic meter.

Multiplying the specific value of wattage by the volume of the room, we get the value of the required power for this room.

As there are household appliances in the building and people are there, wattages are added to the figure:

• for the computer is 0.25-0.3 kW;
• for household appliances - 30% of the nominal value of power consumption;
• for humans - 0,13 kW.

Important! For our example( suppose the height of the room is 2.7 m).

Then the room volume will be 20x2.7 = 54 cubic meters:

• For a room with an average illumination specific cooling capacity corresponds to 35 W / cubic meter.
• If there is a person with a computer in the room, the wattage of the air conditioner will be: Q = 35х54 + 130 + 300 = 2320 W.

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How to calculate air conditioning with additional factors?

There are a number of factors that influence the microclimate in the room. In order not to be in a situation where the split-system "plows" round the clock without turning off, it is necessary to take into account such factors:

• The room is located on the last floor.
• Presence of translucent roof or panoramic glazing.
• A large number of people in the room( this is relevant for offices).
• Frequent ventilation of the room.
• A large number of units of office equipment or household appliances.

Important! In these cases, the calculated wattage is increased by applying the coefficients 1.2-1.5.

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Making the final choice

So, in the calculation, the calculated value of the capacity of the refrigeration unit is 2320 W.But we must also take into account that the technology, working 24 hours a day, will quickly fail.

Important! To operate the air conditioner in gentle mode, it is necessary to provide a power reserve. The value of it, as a rule, is from 15 to 20 percent of the calculated value. In our case, it will be: 2320 x 1.15 = 2670 watts.

In the technical documentation for the product, you can see the characteristic indicated in the British heat units. Here is the correspondence of the capacity of air conditioners in Watts and British units:

• 2100 W - 7 BTU - for premises up to 20 "squares".
• 2600 W - 9 BTU - 20-25 m2.
• 3500 W - 12 BTU - 25-35 m2.
• 5200 W - 18 BTU - 35-50 m2.
• 7000 W - 24 BTU - more than 50 m2.

Important! This information can be used for approximate calculations of the refrigeration power of the split system.

The methods given in the article make it possible to calculate the air conditioner very, very approximately. If you want to make an accurate calculation, but are not sure of your own knowledge, it is advisable to consult a specialist.