Selection of an air conditioner for the home: power calculation

Long-term high-quality operation of climatic equipment is ensured by its informed choice. How to choose the right air conditioner for an apartment in terms of volume and other parameters of the room? What should be considered first?

How to choose the type of split system for an apartment and a house

It is necessary to immediately determine the type of refrigeration machine. Window and mobile monoblocks will not be considered in this article, since their purchase is justified only in extreme cases. Split systems with two units (external and internal) are characterized by division into types relative to the design of the room module.

In standard living rooms, household wall-mounted air conditioners are taken, the indoor unit of which is hung on the wall closer to the ceiling. In rooms with a complex configuration or with a large glazing area, where the wall module cannot be fixed, they acquire a universal split system. It is also called console or floor-ceiling. The unit is mounted either just above the floor on the wall or to the ceiling.

Cassette and duct air conditioners are purchased for rooms with high ceilings and a large area. Most often they are used where it is planned to cool / heat several separate zones. But this already refers more to the selection of an air conditioner for the house, and not in the apartment. Column split systems in residential premises are very rarely installed, since they have high cooling capacity and powerful airflow. Sometimes you can find column air conditioners in country houses in a large living room or dining room.

All types of air conditioners, except for wall-mounted air conditioners, belong to a semi-industrial (commercial) type of climatic equipment.

Design and installation conditions for air conditioners

The choice of the type of split system is closely related to the design and installation conditions. Somewhere you may need an elongated track or an increased height difference between the blocks of the system, someone needs super thin internal modules to fit them into small gaps between windows. Some users manage to squeeze a compact air conditioner between the riser and the wall.

If the question arises of how to choose an air conditioner for the house so that the interior is not disturbed and the installation does not cause problems, they pay attention to the non-standard series of split systems. LG has such, Gree, DAIKIN, MITSUBISHI ELECTRIC, PANASONIC, McQUAY.

Calculation of the power of the air conditioner

The fundamental factor when buying is the selection of the capacity of the split system. Power does not mean energy consumption, but cooling capacity, which is indicated in the technical data sheet and on the nameplate of the device itself. For an apartment and small office buildings, there are simple calculation formulas.

In a simplified version, you can choose the right air conditioner in terms of power as follows: every 10 m² of the room corresponds to 1 kW of cold.

It is also important to take into account the heat surplus coming from people, equipment, lighting devices, windows and doors located there. If the room is on the upper floor, on the sunny side or has panoramic glazing, then, accordingly, the supply of excess heat will be excessive, and the air conditioner will have to suppress it in an enhanced mode.

In a simplified version of calculating air-conditioning equipment, all heat flows are assigned from 15 to 30% of additional power. When the premises are located on the north side, not on the top floor, and the number of people and working equipment constantly staying there is limited, it is enough to lay 15% on the main figure obtained.

For example, a room has an area of ​​20 m². It is home to one person who uses one computer and one TV. The window faces north-west, does not open often. The last floor. It turns out that without taking into account heat gains, it is enough to take a split system with a capacity of 2 kW, and when they are taken into account, it is necessary to add another 20% of 2 kW. The end result is a suitable cooling capacity of about 2.5 kW - this corresponds to model 9 of the air conditioner.

The second way is more difficult. It is used for more accurate calculations when selecting an air conditioner for an apartment. What is taken into account here? It:

• room volume (ceiling height, room area);
• all heat gains (people, animals, lighting, walls, ceilings, windows, doors, equipment).

The general calculation formula looks like this:

Q = Q₁ + Q₂ + Q₃

Q₁ - this is the heat released through the window and roof, walls. The values ​​are calculated by the formula: Q₁ = V * q, where V is the volume of the room, and q is the heat transfer coefficient. Usually, for the southern and northern sides, q is 0.04 and 0.03 kW, and for sides with an average heat input, it is 0.035 kW. The volume is calculated by the formula: V = S * h, where S is the area, and h is the height of the ceiling.

Q₂ - these are heat surpluses from technology. On average, the heat inflow from a working device is 30-40% of the rated power. Add up all the values ​​and get the final result.

Q₃ - this is the heat release of people. In a state of calm, average employment and severe physical stress, a person, respectively, will emit 0.1; 0.2 and 0.3 kW.

To simplify the selection of an air conditioner by the volume of the room and heat gains, you can use the online calculator, where you just need to enter all the values ​​in the appropriate columns and click the "get the result" button.

Air conditioner functions: cold or cold + warm

What other criteria are used to choose a cooling device? Taking into account the needs not only for cold, but also for warmth will help to choose the right air conditioner for an apartment. If a person intends to warm up with it in the fall before turning on the heating, then they buy a reversible model. In another way, they are called air conditioners operating in heat pump mode.

To choose an inverter or start-stop air conditioner?

Often the buyer asks the question of which air conditioner to choose: on / off (start-stop) or inverter. If the plans include frequent operation of the system and not only in autumn, but also in winter, then the second is preferred. Inverters have a wider range of operating temperatures, and smooth control of the compressor allows the device to operate more quietly and more economically. The start-stop model is cheaper to repair though, as it has less complex electronics.

Main technical characteristics of air conditioners

It is important to choose the correct air conditioner according to the parameters indicated below:

• power consumption;
• energy efficiency;
• the noise of both units.

All these data are indicated in the technical data sheet of the device and on the nameplate.

Power consumption shows how much the device consumes on average per hour. Energy efficiency (ERR / COP) is the difference between consumption and output of cold or heat. The higher these values ​​are, the more productive and economical the equipment works.

For modern air conditioners, this figure sometimes exceeds 3 kW, and the manufacturers DAIKIN and MITSUBISHI ELECTRIC have released several series of inverter split systems with an energy efficiency of 4-5 kW.

The noise for the indoor unit should not exceed 30-32 dB in normal mode and 25-27 dB at night, since these are the indicators that the human ear normally perceives.For the outdoor unit, these values ​​can be increased slightly.

Air conditioning cleaning system

When wondering how to choose an air conditioner for an apartment, they pay attention to the filtration system. As a rule, modern split systems are equipped not only with coarse mechanical "screens", but also with fine filters that trap bacteria, viruses and fungi. These include antibacterial, catechin, plasma, charcoal and deodorant systems.

Mechanical filters can be cleaned by yourself once a month. Fine cleaning systems must not be exposed to the same effect. It is worth remembering that over time, any filter loses its quality, so it needs regular replacement.

Additional functionality

Speaking about a properly selected air conditioner in all parameters, they usually mean precisely selected additional functions of climate technology. What can be equipped with a split-system in addition to standard modes?

Most often, in the characteristics of the air conditioner you can find:

• turbo mode - accelerated achievement of the set parameters at maximum power at the beginning of work;
• defrosting mode - when a large amount of snow or ice accumulates on the heat exchanger of the outdoor unit, its automatic defrosting is activated;
• night mode - the device spends less energy to reach the desired temperature and makes less noise;
• self-diagnosis - when the air conditioner is turned on, it tests all its settings and detects malfunctions, if found, it issues error codes;
• automatic mode selection - various sensors control temperature, humidity and other air parameters, relative to which the system itself selects the required mode;
• self-cleaning function - after completion of work, the air conditioner automatically dries the heat exchanger and the fan, thereby killing bacteria and fungi that multiply in high humidity conditions.

The more complex automation in the air conditioner, the higher its cost. Whether all these "tricks" are needed in everyday use, it is up to someone who is puzzled to select an air conditioner for an apartment or house.

Home air conditioner manufacturers

Several dozen manufacturers today offer a huge number of split systems with various designs and a whole list of advantages in technical data. How to choose the right air conditioner for an apartment, based on the reputation of the manufacturer?

To determine the brand of the split system, you can read the information on the rating of manufacturers of climate control equipment. Can you choose an air conditioner for your home for a reasonable price, but with normal build quality and working accessories? in this case, it is worth choosing among business-class devices, such as MDV, SHARP, PANASONIC, TOSHIBA and the like. Be sure to look at the country of assembly. It is better not to take Chinese devices. Most often, complaints are received against them: a strong smell of cheap plastic, vibration and noise, compressor or board breakdowns, manufacturing defects, and so on.

Split air conditioning in a private house

It is much more difficult to choose an air conditioner for a home where there are a large number of separate residential and non-residential areas. Most buyers do not want to clutter the facade of a building with many outdoor units, so they prefer a multi-split system that can combine one outdoor unit with several indoor modules of various types.

Modern multi-split systems have the same characteristics as two-component units: energy efficiency, low noise, high efficiency, compactness, a long freon line and permissible height differences of tens of meters. They work on modern brands of freon, which do not contain chlorine.

In simpler versions, fixed layouts are used, consisting mainly of wall units. When choosing an air conditioner for a house with many rooms of completely different configurations, with different ceiling heights, glazing area and unequal requirements for the permissible temperature, preference is given to multi-split systems with free configuration.

In inverter systems, the total capacity of all indoor units may exceed the rated values ​​of the outdoor unit by 30%.

Powerful high-pressure duct-type air conditioners, built into the under-ceiling space together with the distribution duct system, can also cope with the task of air conditioning in the house. The indoor unit is often sewn up in a utility room, and the treated air easily reaches the required rooms through heat-insulated channels.

The main advantage of a ducted air conditioner in the house is the ability to supply air from the street. Of course, this is not done by the air conditioner itself. A supply unit is required for mixing.

In multi-storey country houses, it will not work to choose an air conditioner on your own, since complex schemes for calculating the power, the length of the route, the location of all components relative to each other and other electrical appliances in the dwelling are used.

In large houses, multi-zone split systems with dozens of indoor units or chiller-fan coil systems with a pumping station and supply and exhaust ventilation are often installed.

Regardless of the type of dwelling in which the air conditioner will be located, it is advisable for the future owner to contact specialists who will help to choose the right unit for all the nuances of the room and the wishes of the buyer himself.