Comparison Daikin ATXC20B/ARXC20B 20 m² vs Daikin Sensira FTXB20C/RXB20C 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.

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 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.

The type of refrigerant used in the air conditioner.

The refrigerant is a volatile liquid that transfers heat between the outdoor unit(s) and the indoor unit(s). In common parlance, such compounds are also called freons, although this is not entirely technically correct. The type of refrigerant is most important when buying air conditioner units separately — for example, to assemble a multi split system (see "Type"): all units must use the same type of freon, otherwise they will be incompatible. However, there are quite noticeable physical differences between different compositions, sometimes quite important.

The most common refrigerants nowadays are R22, R32, R407C, R410A, R134A and R290, here is a more detailed description of them:

— R22. The "oldest" of the varieties of refrigerant found nowadays. It is distinguished by its low cost, and low operating pressure (which has a positive effect on the reliability and price of the cooling circuits themselves). And uniform composition, which makes it possible not to change it entirely in case of a refrigerant leak, but simply replenish the system with the required amount of liquid. However, R22 is environmentally unsafe (mainly for the ozone layer), which is why nowadays it is gradually being replaced by more advanced compounds.

— R32. A fairly advanced refri...gerant that combines three key advantages: efficiency, environmental friendliness and uniformity. So, air conditioners under R32 can be made quite compact and, at the same time, powerful; this substance does not destroy the ozone layer and does not have a significant effect on global warming; and a homogeneous composition allows you to refuel the air conditioner without problems in case of a leak. The main disadvantage of models with this type of refrigerant is the high price associated not so much with the cost of the R32 itself but with the specific requirements for the design of the refrigeration circuit.

— R407C. A refrigerant designed as a safe alternative to R22; does not affect the ozone layer. At the same time, such a composition is much more expensive; its working pressure is slightly higher, which requires a greater strength of the cooling circuit (although not as high as for R410A); and polyester oil used with R407C tends to absorb moisture and lose properties. In addition, this filler is zeotropic (heterogeneous in composition): its components have different boiling points and different evaporation rates. As a result, even with a small leak, the refrigerant loses its properties, and the situation can be corrected only by a complete refilling of the air conditioner.

— R410A. Another green alternative to R22. Unlike R407C, it is azeotropic — it consists of components with the same evaporation specs; so in the event of a leak, the ratio of these components does not change, in which case refilling the circuit is allowed instead of completely replacing the contents. On the other hand, R410A is characterized by high operating pressure, which puts serious demands on the strength and reliability of the cooling circuit and increases its cost; and the refrigerant itself is quite expensive.

— R134A. One of the modern refrigerants with advanced properties. It is completely homogeneous, like R22, but at the same time, it is safe for the ozone layer and is characterized by a low coefficient of influence on global warming. The disadvantage of this composition is traditional — high cost; in addition, it uses polyester oil, which is prone to moisture absorption.

— R290. Liquefied propane is used as a refrigerant. It has several advantages: non-toxic, environmentally friendly (zero impact on the ozone layer, minimal impact on global warming), homogeneous (i.e. does not require complete replacement in case of leakage, it is enough to replenish the missing amount), used with mineral oil, which is insensitive to moisture. In addition, propane has a low operating pressure, which simplifies the design of circuits and reduces their cost, as well as a low temperature at the outlet of the compressor, which contributes to efficiency. This refrigerant has two disadvantages: flammability and high compressor power requirements, which makes such units quite heavy and bulky. Therefore, despite all the advantages, R290 is used quite rarely.

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.

The heating coefficient COP provided by the air conditioner. It is calculated as the ratio of the heat output of the air conditioner in heating mode to the electricity consumption. For example, if a device consumes 2 kW and produces 5 kW of thermal power, then the COP will be 5/2 = 2.5.

The higher this indicator, the more economical the air conditioner is and the higher its energy efficiency class when heating (see below). Each class has its own clear COP requirements.

Note that COP values are usually higher than the values of another important coefficient — EER (see above). It is due to the technical features of the air conditioners.

It is also worth mentioning that since 2013, a more advanced and closer-to-practice coefficient, SCOP, has been put into use in Europe. See "Energy efficiency SCOP (heating)" for more details.

The seasonal SEER cooling factor provided by the air conditioner.

The meaning of this parameter is similar to the cooling coefficient — EER (see above): we are talking about the ratio of useful power to spend, and the higher the coefficient, the more efficient the device is. The difference between these parameters lies in the measurement method: EER is measured for strictly standard conditions (outside temperature +35 °C, workload 100%), while SEER is closer to reality — it takes into account seasonal temperature fluctuations (for Europe) and some other specific points, such as the increased efficiency of inverter compressors. Therefore, since 2013, it is customary to use SEER as the main parameter in the EU; this parameter was also adopted for air conditioners supplied to other countries with a similar climate.