- Functionality of air conditioners
- Calculation of the cooling capacity of the climate system
- Simplified calculation of the cooling capacity of an air conditioner
- Detailed calculation of the cooling capacity of the air conditioner
- Air conditioner efficiency factor
- Constructive and installation types of air conditioners
- Monoblock conditioners
- Split systems
- Inverter or linear air conditioners
- Choosing an air conditioner by manufacturer and cost
Air conditioning in hot summer, especially in a city full of exhaust gases and dust, is no longer a luxury, but a necessity. But how do you choose the best one for your situation? We will talk about how different designs differ, how to choose the right cooling capacity for the area of the room, as well as about leading manufacturers and prices on the market..
The choice of an air conditioner for a house or apartment is to determine the functions that climate systems in your house should perform, the required “refrigeration” capacity and the optimal ratio of the cost of units, the reliability of their design and the amount of comfort that they can provide.
Functionality of air conditioners
The main function of climatic household systems is to cool the living space. Other modes of operation expand their capabilities.
So, the main tasks of climate systems are:
Heating, as a heating mode, cannot be the main one. It is more commonly used in cool weather before or after the heating season. A dehumidification regime is desirable in humid climates to improve heat tolerance for most people. Humidification is necessary in a dry climate, because the air conditioner, even without a dehumidification mode, partially performs this function. And excessively dry air is harmful to the human respiratory system. Some models, unlike most, allow you to organize the flow of fresh outside air.
Additional operating modes of the air conditioner can be:
- sleeping mode;
- air ionization;
- comfort mode;
- air cleaning;
- 3D air flow;
Sleep mode reduces power consumption and compressor noise by reducing fan speed. Comfort mode is an uncommon feature in which the mode control system decides on the optimum temperature. Air purification in various models can be implemented using coarse or fine filters, as well as special purifiers (electrostatics, absorption, etc.).
The 3D airflow function in some models means the ability to adjust the flow not only up / down, as in most cases, but also left / right. Sometimes the direction of the cool air is set by the control panel – the flow will be directed towards it. The purpose of the timer is to set the start and stop of the climate system. It’s nice to come home and immediately feel the desired coolness. Self-diagnosis is a preventive function that determines, if necessary, the cause of a malfunction.
Calculation of the cooling capacity of the climate system
To select the correct air conditioner, you need to calculate its cooling capacity. For a house and an apartment, the calculation can be carried out according to a simplified scheme – depending on the area of the room. More detailed calculations take into account additional heat transfer parameters..
Simplified calculation of the cooling capacity of an air conditioner
Climate systems are almost always labeled with numbers that indicate its cooling capacity in thousands of British thermal units (BTU). With simplified calculations, it can be assumed that 1 kW of cooling capacity is sufficient for 25-30 m3 or 10 m2 premises. A simplified calculation for household systems is shown in table 1.
|Optimal area, m2||power, kWt||Capacity, thousand BTU / h||Common name|
|up to 15||1.6||five||five|
|up to 20||2.0||7||seven|
|up to 25||2.6||nine||nine|
|up to 35||3.5||12||–|
|up to 50||5.2||18||–|
Detailed calculation of the cooling capacity of the air conditioner
A more detailed calculation includes many factors:
- the number of people in the room;
- the height of the ceilings;
- sunny or shaded exterior wall;
- dimensions of openings and glazing area;
- heat release from household appliances, lighting devices;
- number of storeys, etc..
For a residential building or apartment, you can use the following algorithm:
- To take into account the height of the ceilings, a ratio of 1 kW per 25-30 m is used3, where the volume of the room is the multiplication of the area by the height.
- Each person contributes 100-130 W.
- The power of household appliances, electronics, light bulbs – according to the passport, taking into account the heat release coefficient – 0.3.
- Radiation through the windows comes from 200-300 W on the sunny side, up to 50-100 W in the shade.
- If you want to have a guaranteed 18 ° C in the heat, you can increase the received power by 15%.
The calculation of the capacity of the air conditioner for a hypothetical case is given in table 2.
|Parameter||Cooling capacity, kW|
|Power related to the volume of a room with an area of 15 m2 and a height of 2.5 m||1.25-1.50|
|Heat dissipation from 3 people||0.3-0.39|
|Heat dissipation from electrical appliances||~ 0.65|
|Heat penetrating through windows||0.12-0.20|
Air conditioner efficiency factor
The efficiency factor (EF) is an important indicator that reflects the ratio of the cooling capacity to the electrical capacity in the meter. The higher the EC, the less you have to pay for cooling the room. Values from 3.0 are a good indicator. In this case, for every 3 kW of cooling power, 1 kWh of electrical energy is consumed.
Constructive and installation types of air conditioners
The classification of domestic air conditioners is based on their design, installation method and control principles. According to the modular design, air conditioners are divided into monoblock and two-block – split systems. At the place of installation and structurally monoblock are subdivided into window and floor (or mobile) systems, and split systems into wall, ceiling, cassette and duct systems. Depending on the control principle, a distinction is made between inverter and linear air conditioners..
Devices in which all units are concentrated in one housing are called monoblock. Most often they are installed in offices or industrial premises, but they are also successfully used in apartments and private houses..
Window air conditioners
Such units are built into the window opening. Everything is quite simple if the frame is wooden, without a glass unit. When installing in a double-glazed window, it will be necessary to replace one sash with a sandwich panel or another sash with an insert from a sandwich panel. Window air conditioners, as a rule, belong to the budget segment and do not have advanced functions. Some models, in addition to cooling air, supply a limited amount of it from the street, ventilating the room. Design flaw – a sufficiently high noise level.
Window air conditioner
Floor air conditioners
A device of this type is installed on the floor near the window, and the corrugated air duct is brought out of the room in one of the following ways:
- fits between the ajar sashes of the window;
- cuts into glass with sealing joints;
- cuts into a sandwich panel insert.
Installation of a floor-standing air conditioner with an insert in the window
The portable air conditioner is convenient for its mobility. You can move it between rooms, or you can, leaving a city apartment for a dacha, take it to a country house and easily connect there. Such units are compact enough, aesthetic and can have a variety of functional capabilities..
Among the disadvantages, one can single out increased noise, power limitations, low CE and a rather high cost..
Two blocks of the system, interconnected by a refrigerant line, can have different designs and installation locations.
Wall mounted air conditioners
The most popular type of split systems. The unit with the evaporator is mounted on the wall, and the second, compressor unit, is mounted on the outside of the building. The split system can have all the basic and additional functions, except for ventilation. It is a quiet operating device with high CE (especially inverter models). Another important advantage is the beautiful design of the apartment block..
Installation of a wall split system
Rather high requirements for the installation of the installation and the extension of guarantees to the equipment only when these works are performed by a professional organization, makes self-installation undesirable.
Floor and ceiling systems
Floor-to-ceiling air conditioners are versatile systems mounted in large enough rooms, but with ceilings not higher than 3 m. Their indoor unit can be mounted on horizontal (only on a rigid frame) and vertical surfaces. One of the main advantages of the design: a pleasant microclimate in the room. Air moves along the mounting surface, washing it.
Ceiling air conditioner
Cassette and duct air conditioners
Both split systems are united by the installation site – a suspended (wired) ceiling. Both of these devices are semi-industrial and can be used as household devices for large rooms..
Cassette systems supply cooled air through the lower front panel of the evaporator unit. At the same time, air flows are directed in all four directions, which makes the conditioning process even and soft. When assembled, the evaporative unit of the air conditioner looks like a cassette inserted into the ceiling.
Concealed installation of cassette air conditioner
Ducted split systems direct the outgoing stream of cool air through the side panel of the indoor unit, so that they can be built not only on a flat ceiling, but also in decorative “steps” of the ceiling structure. Such air conditioners can cool two or more rooms in a house through diluted air ducts. The great advantage of the ducted split system is the possibility of introducing portions of outside air.
Concealed duct system installation
Inverter or linear air conditioners
Inverter air conditioners differ from simple (linear, start-stop) structurally and control systems. In conventional systems, switching off and on (start and stop) occurs periodically, while the temperature curve in the room looks like a zigzag (broken line), and the air conditioner always works at full capacity when switched on. In inverter regulation is smooth and continuous.
Comparison of temperature conditions with inverter and inverterless control
The name “inverter” means the principle of operation of the electrical system of the equipment – constant transformation of alternating current into direct current and vice versa, while cooling capacity and consumed electricity are constantly changing.
Inverter units have a board – an electronic control system, which, as a rule, is enriched with “smart” functions:
- accounting for weather conditions;
- sensors for determining the position of a person or a remote control in the room;
- protection against voltage changes in the network (highly desirable for delicate electronics of these systems).
The advantages of inverter split systems:
- Does not give too cold streams, more gentle to health.
- Quickly reaches temperature and maintains it more accurately.
- Low noise.
- Higher energy efficiency – in cooling mode up to 60%, in heating mode up to 45%.
- Due to the smooth operation, there are no starting currents affecting the power grid and there is less wear of elements.
The disadvantage of inverters is the higher cost of equipment and its repair in case of failure of the control board.
Choosing an air conditioner by manufacturer and cost
Mitsubishi, Daikin, Toshiba and General are considered to be the best HVAC equipment manufacturers. They have the highest efficiency ratios, reliability levels, and functionality. But this quality is followed by a fair, as a rule, not a budget price. Panasonic, Hyundai and Haier are leading in the category “good quality for an affordable price”. When choosing an air conditioner, you should also take into account all the functionality inherent in various models.
For a preliminary assessment, we made a selection of proposals that were relevant for April 2016 and tabulated them. For a correct comparison, only systems were taken with a capacity not exceeding 4 kW.
Table 3. Air conditioners with a capacity of 2–4 kW, room area 12–35 m2
|Manufacturer||Model||A type||Energy efficiency coefficient||Cooling capacity, kW||Heating power, kW||Area, m2||Inverter||Price, rub.||Installation cost, rub. *||Warranty, year|
|Haier||Home HSU-07HEK203 / R2||wall||–||2.1||2.25||20||not||17200||7500||3|
|DANTEX||RK-07SDM3 / RK-07SDM3E||wall||3.61||2.2||2,3||21||not||18100||7500||2|
|ELECTROLUX||EACS-07HN / N3||wall||–||2.2||2.39||20||not||18400||7500||3|
|MIDEA||MS11D-09HRN1 / MO11D-09HN1||wall||3.01||2.64||2.64||24||not||20,000||7500||3|
|PANASONIC||CS-YW7MKD / CU-YW7MKD||wall||3.5||2.1||2.1||21||not||22500||7500||3|
|Haier||Lightera DC Inverter HSU-12HNF03 / R2 (DB)||wall||–||3.5||3.85||35||Yes||26600||7500||3|
|TOSHIBA||RAS-07SKP-ES / RAS-07SA-ES||wall||3.35||2.08||0.62||20||not||28300||7500||3|
|MITSUBISHI||HEAVY SRK20HG-S / SRC20HG-S||wall||3.64||2.07||2.22||20||not||30500||7500||3|
|KENTATSU||KSGM26HZAN1 / KSRM26HZAN1||wall||3.62||2.64||2.93||25||Yes||32800||7500||3|
|DAIKIN||FTYN25L / RYN25L||wall||3.61||2.65||2.8||25||not||34000||7500||3|
|HITACHI||RAS-10AH1 / RAC-10AH1||wall||3.63||2.65||2.9||26||not||34200||7500||3|
|FUJITSU||ASYG07LLCA / AOYG07LLC||wall||4.29||2.1||2.7||20||Yes||35100||7500||4|
|DAIKIN||FFQN25CXV / RYN25CXV||cassette||3.35||2.8||2.8||25||not||54700||8500||3|
|MITSUBISHI ELECTRIC||SEZ-KD25VAQ / SUZ-KA25VA||channel||3.61||2.5||3.0||25||Yes||99800||7500||3|
|DAIKIN||FLXS25B / RXS25K||floor-ceiling||3.63||2.5||3.4||25||Yes||103200||7500||3|
|MITSUBISHI ELECTRIC||SLZ-KA25VAL / SUZ-KA25VA3||cassette||3.00||2.5||3.0||25||Yes||106500||7500||3|
|FUJITSU||AGYG12LVCB / AOYG12LVCN||floor||4.4||3.0||4.0||35||Yes||167400||8500||4|
|DAIKIN||FTXZ25N / RXZ25N||wall||5.9||2.5||3.6||25||Yes||183000||7500||3|
* standard installation, online store offer