Recommended room area
A very conditional parameter that slightly characterizes the purpose by the size of the room. And depending on the height of the ceilings, layout, structure of the building and equipment, the actual values may differ significantly. Nevertheless, this item represents the maximum recommended area of the room for using the air conditioner in the main mode – 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").
Functions
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.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.Min. T for cooling mode
The lowest outdoor air temperature at which the air conditioner can operate normally in cooling mode.
The need for air cooling arises not only in hot weather — for example, efficient heat dissipation is constantly needed in closed rooms with a lot of heat-generating equipment (such as server rooms). And the limitation on the minimum outdoor temperature is because a large temperature difference between the condenser (heater) of the outdoor unit and the environment can damage the circuits.
Note that in domestic air conditioners, this limit can be quite high — +20 °С and even higher (up to +25 °С); however, additional cooling is usually required for warmer weather, and such air temperatures are not so high as to cause significant discomfort. But in professional units, the minimum temperature for the cooling mode can be significantly below zero — up to -40 °C and even lower.
It is also worth mentioning that in the presence of a heating mode, the permissible temperature for it is noticeably lower than for the cooling mode. It is due to the difference between the formats of the air conditioner in these modes.
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).
Indoor unit dimensions (WxHxD)
Dimensions of the indoor unit of the air conditioner in height, width and depth.
These dimensions allow you to estimate how much space you need to place the device. In this case, of particular importance — mainly for split and multi split systems with wall mounting is the width of the indoor unit. The fact is that in terms of the height and depth of the internal blocks, most of these systems differ slightly in general but the differences in width are much more noticeable. So, the narrowest models have a width of
76 – 80 cm or
less, and the largest ones occupy
91 – 95 cm, and often
more. At the same time, the more powerful the air conditioner, the wider it is, usually, but there is no rigid dependence here.