The first inverter air conditioners appeared a little over 40 years ago and were sold only in Japan, but today everyone can buy an inverter air conditioner with installation inexpensively. Budget models for small spaces, up to 20 m2, cost about 300 usd. Conventional, non-inverter air conditioners are cheaper, but they consume more energy and are inferior in many ways to inverter air conditioners.
How does a regular air conditioner work?
Traditional air conditioners do not provide the ability to regulate the speed of the compressor shaft. Therefore, after switching on, the compressor shaft rotates at a constant high speed, the equipment consumes the maximum power provided for this model. When the air in the room is cooled or heated to the set temperature, the compressor turns off. The main distinctive features of START-STOP type air conditioners (non-inverter):
- temperature is maintained by periodically turning the compressor on and off, therefore it constantly fluctuates, its deviations from the set value reach 2°;
- operating cycle consists of periods when the compressor is running at full capacity and periods of shutdown. The total energy consumption throughout the cycle is quite high;
- frequent starts lead to compressor wear;
- operation at full power is accompanied by noticeable noise, especially noticeable when turned on;
- almost all split systems of this type can operate in heating mode until the outside temperature drops below -7°C. And only in recent years have several series of non-inverter air conditioners appeared with the ability to operate for heating at temperatures down to -15°C.
How does an inverter air conditioner work?
The key feature of an inverter air conditioner is the presence of an inverter in the design. This is a device that is capable of changing the frequency of the current, and through it, the speed of the compressor. Accordingly, the compressor operates with a variable load, and the voltage it actually consumes during operation is often less than the rated voltage. The main differences between air conditioners of this type and traditional ones:
- temperature, after reaching the set value, is maintained because the compressor constantly operates at low speeds. Thanks to this, temperature control is very accurate; a person does not feel deviations within 0.5°C;
- equipment consumes maximum power only at the beginning of the operating cycle, when the compressor shaft rotates at full speed. For most of the cycle, it continues to operate at low speeds, with minimal energy consumption. The total energy consumption is approximately 30% lower than when working with cyclic on-off switching;
- equipment and network are subject to maximum load only at the moment of startup after shutdown, and this happens once per operating cycle. Compressor wear is significantly reduced;
- noise level is low most of the time, and most importantly, the sound is monotonous;
- even the simplest inverter air conditioners can be used in “heat” mode at temperatures down to -15. And for some models of heat pumps that are equipped with inverter compressors, the lower limit of the operating temperature range is shifted to -35°C.
