In my Fathers office they use this ac. This 2.0 tonne cooling capacity wall mounted split air conditioner has a rotary compressor and 3.17 EER. It has anti-corrosive-blue fin copper condenser and has the following features like auto restart with memory backup, timer, sleep mode, anti-freeze thermostat and self diagnosis. The noise levels are 47db and power consumption is 1910 watts. They recently bought this, and its very efficient. Price is also good. You can have a look.