A high efficiency air conditioner will save energy and cost less to run. By choosing a system that is the right size for your home, you can avoid paying for energy you don't need.
Compare star ratings
Use the air conditioner's energy rating label to compare the efficiency of different models. The cooling efficiency is shown in the blue band. The more stars, the more you will save on your cooling costs.
For air conditioners with the same star rating and capacity output, use the number in the blue Power Input box in the middle of the label to compare power consumption. The lower the number, the better.
When you get a quote for an air conditioner, ask for the cooling and heating (if reverse cycle) output of the unit in kilowatts (kW) so you can compare different models. If possible, also get the rated input power consumption (in kW) of the unit on its cooling cycle (and heating if the system is a reverse cycle unit).
Buy to save in the long run
Seek professional advice to make sure you get a cooling system that is the right size for the area you'll be cooling.
Refrigerative air conditioners come in both cooling-only and reverse-cycle models which provide both heating and cooling. A high efficiency reverse-cycle air conditioner will save energy and cost less to run.
Look for inverter models as they are quieter to run and give additional energy savings.
Buy a unit with a thermostat and timer so you can use your cooling system efficiently.
Types of cooling systems
If you can't cool your home using passive cooling, it's important to choose the most appropriate active cooling system for your needs.
Ceiling, wall-mounted and portable electric fans can be a cheap and effective way to stay comfortable on warm, humid summer nights.
Evaporative cooling systems draw air through a moist pad, cooling and humidifying the air before it is blown through your house. They are available in ducted, wall-mounted and portable units, and work best in hot, dry conditions. Evaporative coolers are less effective on humid days, and are not well suited to humid climates.
Air conditioners extract heat from the air inside your house and transfer it outside, cooling the air to a temperature determined by a thermostat. They are available in portable, room and ducted systems.