Throughout this region the best temperature for air conditioners during summer is between 26C to 27C. This means that the compressor stops only when the indoor temperature reaches this level. Newair 10 000 Btu Portable Air Conditioner White Ac 10100e Best Buy Air Conditioning Maintenance Portable Air Conditioner Central Air Conditioners In terms of what temperature to set an air conditioner in winter 18 to 20C is ideal for heating. Optimal air conditioner temperature . Winter is stable in these areas which means. To ensure a units maximum efficiency a standard air conditioners temperature in a moderate climate should be set to 25 to 27C for cooling in summer. At these cool and comfortable temperatures your air conditioner will save energy. During the warm weather it is generally recommended that you set your homes cooling system to 78 degrees Fahrenheit when you are home. South East New South Wales North East Victoria and Australian Capital Territory Summer. Everyone has a...