Section 2: What to consider when choosing the right energy-efficient reverse-cycle air conditioner system for your home

Living with efficient and effective heating can bring health, wellbeing and social benefits and help you to feel more comfortable in your home year-round, so it is important to understand how to choose a suitable system for you.

Living with efficient and effective heating can bring health, wellbeing and social benefits and help you to feel more comfortable in your home year-round, so it is important to understand how to choose a suitable system for you.

Average cost of a new system

Like any product, the cost of reverse-cycle air conditioners can vary widely, but it is important to remember that the highest price doesn’t mean that it will be the best choice for you.

It is worth shopping around and looking out for seasonal discounts as the weather changes and in between peak seasons.

Product Affordability

As a guide only, the average cost of an installed 3.5 kW reverse-cycle air conditioner unit that might be suited for a modest sized living room is around $1,700. Of course, this will depend on the type of system – so we encourage you to shop around. It is important to think about this out-of-pocket cost when making your choice.

Factors affecting your reverse-cycle air conditioner running costs

It is likely that an energy-efficient reverse-cycle air conditioner can provide you with the best efficiency for your energy consumption per dollar – especially those with higher energy efficiency ratings.

However, air conditioner running costs depend partly on how much you use it. Likewise, any savings will depend on what heating and cooling you had previously and how much you used it.

For example, when you start using air conditioning in a home that hasn’t had installed air conditioning before, that may result in additional costs.

A home in a warmer climate, like Mildura, will probably have a need for more cooling, and a home in a cooler inland climate like Ballarat will have greater heating needs.

In addition to selecting a high efficiency rated model, installing the right system size for the space that it will be used in will maximise the efficiency, and minimise the running costs. A model with a higher efficiency rating can have lower running costs then a model with a lower efficiency rating in the same sized room.

Running costs are also affected by other factors such as the type of building materials, and whether the room is insulated well, or if the room has draughts to let warm air in or out. These factors are explained further in Section 3: Energy efficiency and getting the most out of your system.

To help you get an idea of what the running costs might be, Sustainability Victoria has calculated estimated average annual running costs for heating and cooling for different room sizes in Melbourne’s climate.

Ways to reduce running costs

In Victoria on average, about 50 per cent of home energy costs go to heating, so the way that you use heating and cooling appliances, as well as how much you use them, contribute to the running costs.

There are ways to use appliances more efficiently, so that you are getting the most out of your system whenever you use it. This means that the more energy-efficient way that you use your system, the more savings you will see over the course of the appliances lifetime.

Try this Household energy action guide from Sustainability Victoria, to get an idea of where you can save energy use with heating and cooling, and in other ways in your home. There is more information in this guide in Section 3: Energy efficiency and getting the most out of your system.

To help reduce your running costs, you can always check for new retail energy offers that suits you better than your current deal and will allow you to get better value from your energy.

The Victorian Energy Compare website can compare energy plans for you.

Why room size is important

Room size is one of the most important factors to consider for heating and cooling.

Installing a system that is too large or small for your space can cause other inefficiencies such as:

  • Models too powerful for the room size may run frequent short cycles to achieve the target temperature. This can result in the room getting too cold or hot, inadequate dehumidification (i.e. not drying the air enough, making the room feel less comfortable), increased power consumption and running costs, and wear and tear on the system.
  • Underpowered models may have to run more often at maximum output, which could dry the air too much and create excessive wear.

This table from CHOICE provides a rough guide for the system size for different rooms sizes, but you should take advice from the approved Supplier when they assess your home.

Room size Capacity
Up to 20 m2 2–2.5kW
20–40 m2 2.5–5kW
40–60 m2 4–6kW
60–80 m2 5–7kW
80+ m2 6–9kW

Location and climate

The amount of energy you need to heat and cool your house depends on the climate at your location. Mildura is significantly warmer in summer so it will need more cooling than other Victorian climates. Ballarat and Alpine areas are much cooler in winter so they will need more heating than other Victorian climates. Inland climates also have a greater daily range of temperatures than coastal climates. For example, coastal Warrnambool and inland Ballarat will have different temperature ranges, because there is less cloud cover in inland climates, and this means that the climate cools down more overnight and heats up more during the day.

In high density residences, such as apartment complexes you may need to consider the impact of noise from reverse-cycle air conditioners on other residents. If you are planning on installing your new system in an apartment, you should contact the owner’s corporation. Owners Corporations are responsible for authorising the location of the air conditioner and any additional requirements or considerations, for installations on common property.

The Environmental Protection Agency also administers legislation and guidance regarding noise from home occupation, including noise from heating and cooling systems. The Regulation 114 of the Environment Protection Regulations 2021 prescribes items and lists times during which noise from such prescribed items is prohibited from impacting noise sensitives areas (such as neighbouring dwellings).