Comparison Daikin Sensira FTXB20C/RXB20C 20 m² vs Mitsubishi Heavy SRK20HG-S/SRC20HG-S 20 m²

The British Thermal Unit (BTU) is used to indicate the rated capacity of air conditioners in cooling mode. The parameter is indicated mainly for split and multi split systems with wall installation. Capacity is indicated in BTU per hour, while 1 BTU/h is equal to about 0.293 watts. The rated capacity of an air conditioner is often a multiple of 1000 BTU. The indicator determines how many thousand BTU/h the air conditioning equipment provides. For example, the marking "9 BTU" here means a unit for 9000 BTU/h or about 2600 watts of effective capacity.

The practical meaning of the capacity is that by BTU you can easily determine the recommended area of a standard room in square meters: just multiply the figure indicated in the characteristics by 3. So, for 9 BTU it will correspond to 9*3=27 m². Note that there is no strict relationship between BTU and watts in this list: for example, air conditioners with an effective capacity of 2360 to 2900 W fall into the same category of 9 BTU. In practice, even such an approximate ratio is enough to understand which air conditioner should be considered for cooling certain area.

Additional features provided by the device.

— Inverter control. The presence of a compressor with inverter power control in the air conditioner. Models without an inverter have only two modes of operation — full power and off, and the set intensity of heating/cooling is provided by turning the compressor on and off for certain periods. In turn, the principle of inverter control is to smoothly change the compressor power, which avoids constant switching on and off. It provides several advantages: minimal wear, no power surges and unnecessary load on the mains, as well as a comfortable (low and stable) noise level. The main disadvantage of inverter models is the rather high cost.

— Timer. A function that allows you to set the time for automatic shutdown of the air conditioner. Thanks to the timer, you can, for example, start the air conditioner before going to bed and fall asleep peacefully without worrying about turning off the device — it will turn itself off after a user-defined time. And in some models, the timer is part of the night mode (see below).

— Auto restart. Automatic restoration of air conditioner settings after a power outage. Simply put, when power is restored, a device with this function will continue to operate in the same mode as before the power outage.

— Air pollution sensor. A sens...or that monitors the presence of smoke, dust and other contaminants in the air passing through the air conditioner. The use of such a sensor can be different: some models can independently start the ventilation mode when pollution is detected, in others the sensor is only responsible for automatic shutdown, and ventilation must be turned on manually. However, this function greatly facilitates the monitoring of air quality.

— Motion sensor. A sensor that monitors the presence of people in the room. Using the location of people in the room, the air conditioner can change the direction of the flow away from people, thereby protecting against drafts. If the presence of people is not detected, then the air conditioner may switch to low power consumption mode and work not at full capacity, maintaining a comfortable temperature, and depending on the implementation of this functionality, it may even turn off if there is no activity in the room for a long time. It helps to save energy and provides an additional guarantee in case the user forgets to turn off the air conditioner manually.

— Vertical blinds drive. Recall that in most models the air outlet has the form of a slot, equipped with two types of blinds — horizontal (usually one), along the length, and vertical, along the height. By default, the motor drive has only a horizontal blind: this allows you to change the direction of the airflow vertically, as well as close the duct during non-working hours. However, some modern air conditioners (mostly wall-mounted, see "Installation") also provide a vertical blinds drive — it allows you to turn them from side to side, changing the direction of the horizontal airflow. It significantly expands the possibilities for setting up the unit for the specifics of the situation.

— Self-diagnosis. The ability to automatically detect malfunctions and errors in the operation of the air conditioner. The specific features of the operation of this function may be different: in some models, the “health” of the unit is constantly monitored or automatically checked at certain intervals, in others, such a procedure is only started manually. Usually, self-diagnostic systems can automatically fix minor problems that do not require external intervention. More serious problems are reported to the user by the device, for example, by an error code on the display.

— Control via smartphone. The ability to remotely control the air conditioner from a smartphone or other similar device, such as a tablet. Usually, for this, you need to install a special application on the device. Such control can be more convenient and intuitive than using the remote control — the application can provide various specific parameters and functions that are not available for the remote control (for example, the schedule of work by day of the week). In addition, through the application, you can monitor the operating parameters of the air conditioner in real time — the set temperature, speed, programme, etc. — and receive notifications of problems. And some models with this feature can even be connected to the Internet — and get access to air conditioning control from anywhere in the world where there is access to the World Wide Web. Connection with the control gadget can be carried out via Bluetooth or Wi-Fi, depending on the model. For some devices, this feature may require the use of an external Wi-Fi module (see below).

— Wi-Fi module connect. Such equipment significantly expands the functionality: a Wi-Fi connection can be used to control via a smartphone or even via the Internet, to transfer statistics and other service data to external devices (smartphone, laptop, etc.), for remote diagnostics and troubleshooting, etc. The specific set of capabilities associated with the wireless module should be specified separately; however, this feature is typical mainly for fairly advanced models. Note that modern air conditioners can be equipped with built-in Wi-Fi modules. However, when buying such a model, you have to immediately pay extra for additional communication options, while with a separate Wi-Fi adapter, there is a choice — you can buy it both together with the air conditioner, and separately, later (or even not buy at all if this function turns out to be unnecessary).

— I Feel (remote control with temperature sensor). The presence of a temperature sensor in the complete remote control. Usually, such a remote control also has a separate button, when pressed, the air conditioner measures the temperature at the location of the remote control, that is, near the user. It allows you to more accurately control the microclimate than when using a sensor on the indoor unit — the device estimates the temperature at the user's location, and not at the installation site of the indoor unit.

Types of additional filters that are standard on the air conditioner (in addition to the simplest mechanical cleaning filters, which are found in all models).

We emphasize that we are talking specifically about the filters supplied in the kit; Some models allow you to separately purchase additional elements for air purification, but this possibility is not taken into account in this case. As for specific options, the most popular in modern air conditioners are ionizers, various antibacterial filters(including catechin elements and UV lamps), devices for fine cleaning (including HEPA filters), antifungal, antiallergenic, deodorizing and formaldehyde filters, and also elements that combine several functions at once (for example, catalytic). Here is a detailed description of each of them:

— Ionizer. The action of the ionizer is based on the saturation of the air with negatively charged ions. They provide a feeling of fresh air, have a bactericidal effect, and are considered beneficial for overall health. One of the advanced types of ionizers are also plasma (electrostatic)...filters. Along with the saturation of air masses with useful air ions, they are assigned the task of air purification. Such filters can quite effectively destroy harmful microorganisms, destroy some harmful substances, and trap grains of dust, smoke, soot, etc. — these particles, under the influence of ionized air, themselves acquire a charge and are attracted to the filter plates.

— Fine cleaning. This term usually refers to advanced mechanical filters that provide air filtration at a microscopic level. The specific effectiveness of such devices may vary; it should be clarified separately in each case. Note also that the HEPAs described below are also, in fact, fine filters; however, they use a specific operating principle and are inherently highly efficient. Therefore, the presence of HEPA filters is indicated separately.

— HEPA filter. A special type of mechanical fine filters. Thanks to the special design of the microchannels through which air passes in such a filter, such devices can trap particles much smaller in size than the size of the microchannels. For comparison, the effectiveness of a HEPA filter is assessed by its ability to capture contaminants measuring 0.1 - 0.3 microns (with such particles, such a filter is least effective), while the size of most bacteria starts at 0.5 microns. Based on their effectiveness, such filters are divided into classes; Nowadays, HEPA classes from 10 (retains at least 85% of the mentioned particles) to 14 (filtration efficiency reaches 99.995%) are relevant.

- Catechin. In fact, it is a type of antibacterial filters described below, created on the basis of catechins - natural organic substances with a powerful antioxidant effect. Such filters are highly effective in fighting bacteria and viruses, but they are not cheap; In light of these features, they are separated into a separate category.

- Catalytic. Most often, this term refers to photocatalytic, or “zeolite” filters - devices that operate using a special substance (photocatalyst) and UV radiation. Under the influence of such radiation, the catalyst decomposes the organic matter falling on it into simpler substances - usually water and carbon dioxide. This technology not only allows you to remove harmful impurities from the air (at the level of individual molecules), but also provides a good bactericidal and antiviral effect. Moreover, such a filter requires virtually no maintenance: the photocatalyst is not consumed during operation, and the reaction products freely evaporate outside. On the other hand, the price of such elements is quite high.

- Antibacterial. Various filters designed to destroy bacteria and other harmful organisms - viruses, fungi, etc. The specific operating principle, level of efficiency and maintenance rules for such filters may vary; these details should be clarified in the documentation for the air conditioner. However, if air disinfection is of fundamental importance to you, such a filter will definitely not be out of place. Let us note only two nuances in this regard. Firstly, catechol elements are usually not included in this category, although they have the same purpose (see above); secondly, not every antibacterial filter is capable of effectively fighting viruses - again, it would not hurt to clarify this point separately.
It is also worth considering that no matter how effective the air conditioner filters are, thorough air disinfection is not its main task; specialized devices should be used for these purposes.

- Antifungal. A specialized filter for removing harmful fungi from the air, such as mold. The antibacterial devices described above also have this function to one degree or another; however, this type of filter is much more effective in this regard. On the other hand, the need to intensively fight specifically fungi does not arise so often, and for other cases, the same antibacterial filters are usually quite sufficient. So antifungal elements are used quite rarely in modern air conditioners.

- Anti-allergenic. Filters designed primarily to remove allergy-causing contaminants from the air: pollen (including from indoor plants), dust mites, particles of pet hair, etc. The specific operating principle of such filters may vary and should be clarified separately. Thus, relatively inexpensive air conditioners usually use simple mechanical cleaning, and the term “anti-allergenic” is more of a marketing ploy than a real description of the filter’s specialization. More advanced models often include more advanced technologies - for example, an enzyme filter that breaks down allergens into simple, harmless substances like water and carbon dioxide.

- Ultraviolet lamp. A lamp that processes the air passing through the air conditioner with UV radiation. This treatment provides a bactericidal effect: ultraviolet light neutralizes most bacteria, viruses and fungi. True, in general the efficiency of such lamps is not particularly high; however, they are a great addition to an antibacterial filter. And even without such a filter, the quality of air purification of an air conditioner with a UV lamp will be higher than that of a similar model without such a lamp.
We would like to emphasize that this function should not be confused with the catalytic (photocatalytic) filter described above - UV lamps have a much simpler design and operating principle.

— Deodorizing (charcoal). A specialized filter designed, among other things, to combat unpleasant odors. Acts at the molecular level, allowing ordinary air to pass through and absorbing molecules of substances that create unpleasant odors; Of course, it is also capable of trapping larger particles, such as smoke. Activated carbon is most often used as a filter element - hence one of the variants of the name; There are filters based on other substances, but they also have similar properties. It is worth keeping in mind that in any deodorizing filter the working element must be changed periodically - when its resource is exhausted, it becomes useless and can even emit harmful substances itself.

- Formaldehyde. A specialized filter for removing formaldehyde and some other harmful organic compounds (for example, ammonia, benzene and/or hydrogen sulfide) from the air. The source of such substances can be both external pollution (for example, emissions from industrial enterprises) and some objects in the room itself: new furniture or curtains, some types of floor and wall coverings (immediately after application), spoiled food, cigarette smoke, etc. n. The specific operating principle of filters of this type may vary. Most often, the so-called cryocatalytic element is used, in which the catalyst decomposes organic matter into simpler, harmless components, and then restores its properties due to the cold when the air conditioner operates for cooling. In addition, many catalytic (photocatalytic) filters (see above) have similar capabilities, so one such element can be declared in the characteristics as two types of filters at once - both catalytic and formaldehyde.

In addition to the varieties described above, other types of filters may be found in modern air conditioners, in particular:

— Air purifying. A general name used for different types of filters. This term often denotes the simplest elements of coarse cleaning (for advertising purposes - so that the list of filters in the characteristics is larger). However, there is also another option - devices created on the basis of specific proprietary technologies and which do not fit into any of the varieties described above; such devices can combine several functions simultaneously (for example, fine filtration and antibacterial effect).

— Dust collecting. Most often we are talking about a simple mechanical filter that traps dust and other relatively large particles. Almost all modern air conditioners are equipped with such devices, but in some models the presence of “dust” filters is specified separately - mainly for advertising purposes.

— With vitamin C. A filter that saturates the air with vitamin C. It is believed that this supplement has a positive effect on immunity and skin condition; There is no clear evidence of this, but in conditions of vitamin deficiency, such a device will definitely not be superfluous.

- Preliminary. Mechanical coarse filter installed in front of the main set of filters. Detains relatively large contaminants, preventing them from reaching other filter elements and removing part of the “load” from them. At the same time, the design of the pre-filter is, as a rule, as simple as possible, and its maintenance is limited to periodic shaking or washing.

— “Ionic” (for example, Smart Ion, etc.). As a rule, it is the same electrostatic filter (see above), but presented under one or another brand name.

Power consumption of the air conditioner in cooling and heating mode; for models without a heating mode, only one number is given. This parameter should not be confused with the effective capacity of the air conditioner. Effective capacity is the amount of heat that the unit can "pump" into the environment or the room. This item also indicates the amount of electricity consumed by the device from the network.

In all air conditioners, the power consumption is several times lower than the effective capacity. It is due to the peculiarities of the operation of such units. At the same time, devices with the same efficiency may differ in power consumption. In such cases, the more economical models usually cost more, but with continued use, the difference can quickly pay off with less electricity consumption.

Also, two points related to electrical engineering depend on this nuance. Firstly, power consumption affects power requirements: models up to 3 – 3.5 kW can be connected to a regular outlet, while higher power consumption requires a three-phase connection (see below). Secondly, the power consumption is needed to calculate the load on the mains and the necessary parameters of additional equipment: stabilizers, emergency generators, uninterruptible power supplies, etc.

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 capacityup 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.

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.

The amount of air that an air conditioner can pass through itself in an hour.

This parameter depends on the power and the overall level of the device, but there is no strict dependence here: models with the same effective capacity may differ in air circulation speed. In such cases, it is worth proceeding from the fact that a higher speed contributes to uniform cooling/heating of the air and reduces the time required to create a given microclimate; on the other hand, higher-performing air conditioners use more energy, are larger and/or cost more.

The maximum and minimum level of noise produced by the air conditioner during operation; for split and multi split systems (see "Type"), by default, it is indicated for the indoor unit, and the data for the outdoor unit can be specified in the notes.

The noise level is indicated in decibels; this is a non-linear unit, so it is easiest to evaluate this parameter using comparative tables — they can be found in special sources. Here we note that, according to sanitary standards, the maximum level of constant noise for residential premises is 40 dB during the day and 30 dB at night; for offices, this figure is 50 dB, and in industrial premises higher volume levels may be allowed. So it is worth choosing an air conditioner according to this indicator, taking into account where and how it is planned to use it.

As for specific numbers, among the quietest modern air conditioners, there are models with a minimum performance of 23 – 24 dB, 22 – 21 dB, and sometimes even 20 dB or less. However, units at 31 – 31 dB and 33 – 34 dB are not uncommon; such loudness, usually, does not create discomfort in the daytime, but at night it is no longer desirable. However, in some cases, a louder air conditioner may be the best choice: noise reduction affects the cost, sometimes quite noticeably, and if the device...is not planned to be turned on at night, you can not overpay for additional noise reduction.

Cooling factor EER provided by the air conditioner. It is calculated as the ratio of the useful operating power of the air conditioner in cooling mode to the electricity consumption. For example, a device that delivers 6 kW of operating power in cooling mode and consumes 2 kW will have an EER 6/2 = 3.

The higher this indicator, the more economical the air conditioner is and the higher its cooling energy efficiency class (see below). Each class has its clear requirements for EER.

It is worth noting that this indicator is considered not very reliable, and in the European Union another coefficient has been introduced that is closer to practice — SEER. See Energy efficiency SEER (cooling) for more details.