Star rating in air conditioners are provided by Bureau of Energy efficiency (BEE) to guide consumer to take informed decision. Rating is done in a scale of 1 to 5, where 5 star represents highest energy efficient appliance and 1 star represents lowest, The star rating helps consumers to take informed decision about the product purchase. the performance parameter for Star selection is based on ISEER, higher the ISEER higher the stars and higher the efficiency.
For understanding basic terminology in air conditioning, Please click here, For information on refrigerants click here. For best air conditioner available in Indian market click here
What is mean by ISEER?
Indian Season energy efficiency ratio is the output of air conditioning system corresponding to Indian season divided by power consumption during same period.
Being India a vast country and various seasonal differences region wise, BEE has formed reference outdoor temperature guideline for Indian region as a whole for measuring output of the air conditioning.
Below table shows reference outdoor temperature bin distribution for Indian climate (Based on 54 cities weather condition across india):-
Test of the air conditioning system is done at 100% loading and 50 % loading at temperature condition shown below in the table:
After measuring Cooling capacity and power consumption, ISEER are calculated as per attached excel sheet.
inverterACmastersheetprotected-1Download
For Unitary(windows) and split AC below table shows range of ISEER requirement to be put product into different star rating categories,
 Labelling of appliances are based on time period, therefore before taking decision on Star rating in air conditioners, it is imported to take a note on the validity of star rating period, With increase on time efficiency of appliances increases and similarly BEE keep on improving standard from time to time,
For window and Split Ac star rating and corresponding ISEER rating is mentioned below for two different period of 2018-2020 and 2021-2023 :
For more detail on energy efficiency program by BEE, Please click here
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