Recommended room area
The area of the room recommended for using the air conditioner in the main mode is for cooling.
Most often, this parameter is indicated by a simplified formula: about 100 W of effective air conditioner power is required per 1 m2 of room area. Thus, for example, for a model with a cooling capacity of 2200 W, the recommended area will be 2200/100=22 m2. However, these results are relevant only for standard conditions in residential and office premises: ceiling height of about 2.5-3 m, no strong heat gain, etc. For more specific situations, there are more detailed calculation formulas, that can be found in special sources. Anyway, choosing an air conditioner according to the recommended area, it's ok to take a margin of at least 15-20%: this will give an additional guarantee that the device will be effective.
The recommended area
up to 15 m2 for a modern air conditioner is considered very low; such units are designed to serve single rooms of a small area. For an average living room like a bedroom or living room, a
20 m2 or even
25 m2 model is better suited. Models of
30 m2 and above are already intended for at least studio apartments, and more often for office and industrial premises. And in the most powerful modern units, the recommended area can be
150 – 175 m2 or even
more.
Note that the same general formula is used for the heating mode — “100 W per 1 m2”. At the same time, the effective power of most air conditioners in this mode is noticeably higher than in the cooling mode. So this item can also be used to select a unit with a heating function: an air conditioner capable of cooling a room of a certain area is almost guaranteed to be able to heat it (taking into account the relevant restrictions on the use — see "Operating modes").
Cooling capacity
The heat output of the air conditioner when operating in cooling mode, in other words, the amount of heat energy that the unit can transfer from the room to the external environment when operating in this mode.
In general, cooling capacity
up to 2 kW for modern air conditioners is considered very modest,
2–3 kW is low,
3–4 kW is medium,
4–6 kW is above average, and in the heaviest and most productive models this figure can be
6–8 kW and even
more. Also, the conventional unit BTU can be used to denote capacity; in our catalogue, 1 BTU corresponds approximately to 0.293 W, however, for the convenience of choice, some deviations are allowed: for example, the
7000 BTU category includes units with power from 1.8 to 2.3 kW. Also on sale you can find air conditioners for
9000,
12000,
18000,
24000 BTU and
more.
As for the choice for this indicator, the simplest formula is as follows: at least 100 W or 1/3 BTU of thermal power should fall on 1 m2 of the area of the room. Thus, to estimate the maximum area served, the power in watts should be divided by 100, and the power in
...BTU should be multiplied by three. However, all these calculations are relevant only for standard residential/office premises with a ceiling height of about 2.5-3 m. For other conditions, you need to use a more complex formula, which is the sum of three parameters: 1) Q1 - the heat gain of the room itself, calculated by multiplying the area of the room by the height of the ceilings and the heat transfer coefficient (it ranges from 30 to 40 W, depending on the conditions); 2) Q2 - heat gain from operating equipment (on average, a third of the total power of all electrical appliances); 3) Q3 - heat gain from each person (from 100 W for sedentary work to 300 W for heavy physical exertion). More detailed recommendations regarding such calculations can be found in special sources.
A special case is represented by separately sold outdoor units of air conditioners (see "In box"). In this case, the capacity in cooling mode is the highest heating capacity of the indoor unit (in the same mode, of course) that can be connected to this outdoor unit. For multi split systems, respectively, the total indicator of all indoor units is taken into account.Heating capacity
The power provided by the air conditioner in heating mode. It is indicated by the amount of thermal energy that the air conditioner can "pump" from the external environment into the room when operating in this mode. The most modest modern units have a heating capacity of
2 – 3 kW or even
less, in the most performant it reaches
6 – 8 kW or
more.
When evaluating this capacity, the same formulas are relevant that are used in calculating the power of traditional heating. So, for the full heating of an ordinary residential or office space (with ceilings of 2.5-3 m and normal thermal insulation), a thermal power of at least 100 W is required. There are more detailed calculation rules that allow you to calculate the necessary characteristics for other conditions. And if we are talking about a separately sold outdoor unit (see "In box"), then the meaning of this parameter is somewhat different. It indicates the maximum power of the indoor unit that can be connected to this outdoor unit to work in heating mode. For multi split systems, respectively, the total capacity of all indoor units is taken into account.
Recall that most air conditioners are not designed for use as full-fledged heating systems. However, such a unit can be a good addition to the main heating system. At the same time, air conditioners are less expensive than el
...ectric heaters: the heater has an effective power equal to energy consumption, and the air conditioner consumes much less energy than it supplies to the heated room.
Also note that the unit BTU (more precisely, BTU/hour) can also be used to indicate the effective capacity (including in heating mode). 1 BTU (BTU/h) initially corresponds to 0.293 W, and the numbers in the characteristics of air conditioners correspond to thousands of BTU/h. For example, a 7 BTU air conditioner will produce an effective capacity of 7000 BTU/h, or about 2 kW. Such marking is convenient because BTU can easily determine the recommended area of a standard room (in m2): just multiply the figure indicated in the characteristics by 3. So, in our example, the power of 7 BTU will correspond to an area of 7*3=21 m2.Display
A small screen installed on the indoor unit of the air conditioner. Such
a display usually has basic functionality and displays a limited set of characters - numbers, some letters, sometimes also individual graphic icons. However, even such a screen can display quite a variety of information: set temperature, operating mode, timer settings, filter status, error codes, etc. Thanks to this, control is more convenient and visual.
—
Hidden display. When switched off, the hidden info display blends in with the surface design of the indoor unit of the air conditioner and remains invisible. In active mode, the characters on the screen are visible through a certain place in the texture and all the necessary information is displayed on the display. On most models, the screen can be turned off using the remote control, and this feature can often be set to automatically hide after a certain period of inactivity, which will be useful at night.
Maximum T for cooling mode
The highest outdoor air temperature at which normal operation of the air conditioner in normal cooling mode is possible.
It should be noted that for basic models of home climate equipment, the max outdoor air temperature for cooling is usually +43 °С. Advanced models of air conditioners remain operational at +50 °С and even at +55 °С (which almost reaches the absolute maximum air temperature on our planet).
