For a comfortable temprature you should look to set your air con unit between 21-22°C. Many go as low as 16°C, but we do not recommend to operate your unit for a prelonged period of time at this low temp. Once you have found your comfortable room temprature, the compressor will maintain it while the fan circulates cool air. Factors that slow this process include a room's initial temperature, daily temperature fluctuations, open doors or windows, people and the number of appliances inside the room that expel heat (like microwaves or computers).