Air conditioning

All split system units have the compressor unit/s located separately from the air outlets and come in a variety of configurations, including standard single head units, multi-head, ducted units or portable units. With the compressor unit located separately, split systems are comparatively quieter than the older style box air conditioners. However, the performance, energy efficiency, noise levels and temperature control capabilities of units in this category can vary significantly between brands and models.

• Inverter systems can run at different capacities in response to the current ambient temperature of the space and can require less energy to maintain room temperature once it has been cooled. Whist usually costing more to purchase than a non-inverter systems, inverter systems are becoming the most common due to them being more efficient and having lower running costs.
• Portable units are available; however these can be much less effective and comparatively very inefficient.
• Ducted systems supply cooled air from an outdoor compressor unit to multiple rooms in the house through an integrated system of insulated ducts running through the roof space or under the floor. These units have the ability to cool the whole house with one system but can be comparatively more expensive to install than multiple split systems and require more energy to run. Ducted systems are more easily and economically installed when building a new home or doing a major renovation.

This style of air conditioner has all of its components in one unit, which can be mounted on a window frame, or for a more permanent installation, into an external wall. They are generally cheaper to purchase than split systems. Their output capacity is lower than a comparatively sized split system, so they are best suited to cooling single rooms or other small areas. Having the condenser located with the unit means they can also be quite noisy.

This style of air conditioner works on different principles to other air conditioning systems by using the cooling effective of evaporation to help cool the air. Evaporative air conditioners add moisture to air sourced from outside buildings and circulate throughout the building. This differs to split or window air conditioners that use a compressor to cool the air, and also remove moisture from the air.

Advantages of an evaporative air conditioner is that they have lower running costs than other systems and do not dry the air, which can lead to dehydration.They do have a requirement for a freshwater connection to the outdoor unit and have different maintenance requirements. Evaporative systems work best in drier inland climates and generally not suited to humid climate zones.

1. Select the right temperature. Stick to 25°C in summer and 18°C in winter. Every one-degree cooler in summer adds around 10%¹ to the amount of electricity the aircon uses – which can quickly add up!
2. Install the right sized aircon for the space you need to cool or heat. Consider factors such as the size of the room, the direction the windows in the room face and whether you have insulation in the ceiling.
3. Choose an aircon with a high energy star rating - for every extra star your aircon has, you’ll save around 15%² in running costs.
4. Insulate your home by installing roof and wall insulation with a minimum R-value to suit your locality. In Queensland, this could range from R4.1 to R5.1 for the ceiling and around R2.8 for the walls³.
5. Maintain your aircon regularly, particularly before the summer cooling and winter heating periods. Follow the manufacturer’s instructions to clean the air filters and coils or consider a professional clean of both indoor and outdoor unit fins and coils for improved energy efficiency and healthier air, particularly if your air conditioner gets regular usage.

1. Use fans to circulate cool air - they’ll help your aircon to distribute cool air to where it’s needed and allow you to set your air con to a higher temperature in summer but still be comfortable.
2. Turn your aircon off when you’re out and wait until you’re back to turn it on again. It should only take around 20 minutes⁴ to cool your home when you return.
3. Select the air recirculate setting when running your aircon. Otherwise, you'll be drawing in much warmer air from the outside and using a lot of electricity to cool it down.
4. Close doors and windows in areas you want to cool to hlp keep the cool air in and the hot air out.
5. Consider using a fan instead. If the weather allows, open your home to create cross breezes and use ceiling fans to keep you cool. It’ll be much friendlier on your pocket too.

1. Prevent heat loss by repairing faulty door seals. Use door snakes and weather-strips to block any gaps where heat can escape.
2. Focus your heating in commonly used rooms and trap in warm air by closing windows and doors.
3. Rug up. Dress appropriately for the weather and check rooms for drafts.