Comparison Panasonic CU-TZ25ZKE 25 m² vs Panasonic CU-Z25ZKE 25 m²

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 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 maximum noise level in decibels (dB) produced by the outdoor (outdoor) air conditioner unit during normal operation.

In household split systems, the noise level from the external unit is usually in the range from 40 to 55 dB. The lower this indicator, the quieter the unit operates and the more comfortable it is to use. Sanitary standards require the noise level for residential buildings from permanent sources to be no higher than 40 dB during the day and 30 dB at night, and in offices background noise of up to 60 dB is completely acceptable. The easiest way to estimate specific noise levels is using comparative tables. So, 40 dB is the level of a quiet conversation or TV at medium volume, 50 dB is approximately the normal tone of human speech, and 60 dB is the level of a loud voice. More detailed data can be found in special sources.

It is important to note that indoors the background noise level from the outdoor unit will be significantly less than outdoors. However, if the noise does not bother you when the air conditioner is running, this does not mean that it does not bother your neighbors. With open windows, the external unit can become a fairly strong source of noise. Therefore, for apartment housing stock it is advisable to give preference to low-noise models of climate control equipment.

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.

Seasonal heating coefficient SCOP provided by the air conditioner.

Like the COP (see above), this parameter describes the overall efficiency of the air conditioner in heating operation and is calculated by the formula: thermal (useful) power divided by electricity consumption. The higher the coefficient, the more efficient the device, respectively. And the difference between COP and SCOP is that COP is measured under strictly standard conditions (outside temperature +7 °C, full workload), and SCOP takes into account seasonal temperature fluctuations (for Europe), changes in air conditioner operating modes, the presence of an inverter and some other options. Thanks to this, SCOP is closer to real indicators, and since 2013 this coefficient has been taken as the main one in the territory of the European Union. However, this parameter is also used for air conditioners supplied to other countries with a similar climate.

The seasonal energy efficiency class that the air conditioner complies with in cooling operation. Initially, this parameter was designated in letters from A(the most economical indicator) to G (the most expensive); however, more efficient classes than A appeared later — A+, A++ and A+++(the more pluses, the higher the energy efficiency).

This parameter is directly related to the value of the SEER coefficient. For more information on this factor and how it differs from the EER, see "Seasonal Cooling SEER Ratio". Here we note that each class has its range of SEER values; detailed correspondence tables can be found in special sources.

Other things being equal, more energy-efficient air conditioners are more expensive, but the difference can be recouped as it uses less electicity.

The seasonal energy efficiency class that the air conditioner complies with when operating for heating. Initially, this parameter was designated in letters from A(the most economical indicator) to G (the most expensive); however, more efficient classes than A appeared later — A+, A++ and A+++(the more pluses, the higher the energy efficiency).

This indicator is directly related to the value of the SCOP coefficient. For more information about this coefficient and how it differs from the COP, see "Seasonal heating SCOP". Here we note that each class has its range of SCOP values; detailed tables can be found in special sources.

Other things being equal, more energy-efficient air conditioners are more expensive, but the difference can be recouped as it uses less electricity.