If you are an electrical engineer, then you might want to specialize in technologies related to home appliances. So you can study a diploma in Refrigeration & Air Conditioning. This will help you in making a career both in India and abroad. In abroad, engineers of air conditioners or other electrical appliances are in high demand. In fact, after this diploma course you can think of pursuing research oriented courses on electrical appliances. You will learn the mechanisms of manufacturing, as well as repairing the air conditioners and refrigerators. So this course will benefit you more if you study this after completing either a degree or diploma in engineering. You will learn about the old and upcoming technologies used for refrigerating and air conditioning. You will get hands on training sessions on these electrical appliances. So you will be able to implement the theory learned on the real life apparatus.