Image (right) Panasonic aircon has a dust sensor
March 15 2017: Split air conditioners are changing over to Inverter technology. What does this mean? Think of the conventional aircon as fixed speed device. Like water taps 50 years ago that were either open or closed. In this case, heat, rather than water is flowing at full speed or not at all. In a regular aircon the compressor is on or off. When the thermostat reaches the set temperature, the compressor stops but the fans continues to work. When the thermostat senses that the temperature has risen, the compressor kicks in again.
An inverter aircon is similar to a modern screw type water tap: you can slow down the flow of water ( or heat) or increase it at will. The compressor is always on but draws less or more power depending on the incoming air temperature and the temperature set in the thermostat. Think of it also like the accelerator in a car. Today only split aircons come with inverters. The word inverter refers to the DC inverter circuit which controls the motor speed.
With inverters becoming popular, India's Bureau of Energy Efficiency has come up with a new rating system to replace the old 1 star to 5 star aircon ratings. It is called Indian Seasonal Energy Efficiency Ratio or ISEER. It is now voluntary for inverter aircons -- but mandatory from January 2018. It takes account of the band of Indian ambient temperatures from 24 degrees Celsius to 43 degrees Celsius. ISEER is a ratio of the total heat that the system removed to the total energy consumed. So higher the number better the performance ( 4.5 for 5 star to 3.1 for 1 star). To learn more about airconditioners before buying, check out a useful site called BijliBachao.com.
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