A 220-volt air conditioner is not necessarily better than a 110-volt air conditioner. The main difference is the power source requirement. A 220-volt air conditioner requires a different type of wall outlet that allows for a greater current of electricity than a 110-volt air conditioner.
Smaller air conditioners often use the 110-volt outlet while higher-powered air conditioners usually require a 220-volt outlet to function, but it's not the volts that determine the cooling power of the air conditioner. Look instead at the British thermal units per hour. The higher the British thermal units, the greater the area that can be cooled by the air conditioner and the more volts the air conditioner needs. Generally, in order to cool a 1,000-square-foot room, an air conditioner with 21,000 British thermal units per hour is required.
Before buying an air conditioner, be sure to check what type of outlet is available and compare it to the specifications of the air conditioner under consideration. If needed, contact a local electrician to modify the current outlet.