Answers to the air conditioning questions homeowners ask us most, grouped by topic. Each answer links to the full guide where there is more to say.
Choosing a system
What is the Zoned Energy Rating Label?
It is the energy label on air conditioners sold in Australia, in place since 1 Apr 2020. It replaced the old single-figure star label.
The important difference is that it rates the same air conditioner separately for three climate zones: hot, average and cold. An air conditioner performs differently in Darwin than in Hobart, and the label shows both.
It gives you:
- Star ratings from 1 to 10, for cooling and heating, in each climate zone
- Estimated annual energy use in kilowatt hours for each zone
- Heating and cooling capacity in kW
- Noise levels in decibels, indoor and outdoor
Find your climate zone using the Energy Rating Calculator, then compare models on the rating for your zone.
Tip: choose the capacity and features you need first, then use the star rating to compare similar models. Star ratings are only comparable between systems of similar size and type.
Which air conditioners have to display the label?
It is mandatory in store for single-phase, non-ducted, unitary or single-split air conditioners up to 30kW.
It is not required for ducted systems, multi-split systems, three-phase systems, evaporative coolers, water-to-air systems, or anything over 30kW. Some manufacturers display a voluntary label on ducted and three-phase models.
It is also not mandatory online, so if you cannot see it on a retailer’s website, ask.
How do I know which type of air conditioner to install?
It comes down to your climate, how many rooms you want to condition, and whether you need heating as well as cooling.
- Humid summers: refrigerated air conditioning. Evaporative loses effectiveness in humidity
- Dry summers: evaporative is a genuine option and much cheaper to run, but it cools only
- One or two rooms: split systems
- Three rooms: a multi-split, a split system in each room, or ducted. Worth quoting both ways
- Four or more areas: ducted, or a multi-split if ducting will not fit
Read our guide to choosing a system, or take our two-minute quiz.
What size air conditioner do I need?
Manufacturers rate capacity in kilowatts. As a rough starting point:
| Room size | Approximate capacity |
|---|---|
| Up to 20m2 | 2kW to 3.5kW |
| 20m2 to 40m2 | 3.5kW to 6kW |
| 40m2 to 60m2 | 6kW to 9kW |
| Whole house | Multi-split or ducted, sized on assessment |
Treat that as a starting point only Ceiling height, insulation, window size and orientation, roof type and your climate all change the answer, often significantly. The right way to size a system is a heat load assessment done on site by your installer.
Bigger is not safer. An oversized system short-cycles, dehumidifies poorly, and costs more to buy and to run.
Is reverse cycle worth it if I only want cooling?
Usually yes. Reverse cycle models typically cost little more than cooling-only models, and they give you the cheapest form of heating available to most Australian homes. Most systems sold here are reverse cycle for that reason.
Cost and running costs
How much does air conditioning cost?
Indicative installed prices in Australia:
| System | Indicative cost installed |
|---|---|
| Single split system | $1,500 to $5,000 |
| Multi-split system | Around $7,700 for a whole home |
| Ducted reverse cycle | $9,000 to $15,000, more for large homes |
| Ducted evaporative | From around $5,000 |
| Window or wall unit | $600 to $1,200 for the unit, plus installation |
| Portable | $300 to $1,100, no installation |
Figures are indicative only. We last reviewed them in October 2026. What you pay depends on your home. Read more about costs
How much does it cost to run an air conditioner?
Work it out from the energy label:
Annual running cost = estimated annual energy use (kWh) for your climate zone x your electricity tariff ($ per kWh)
Your tariff is on your electricity bill.
As a worked example published by the Australian Government’s energy rating scheme (energyrating.gov.au): a reverse cycle single split with 8.5kW cooling and 10kW heating, in a hot climate zone, uses an estimated 2,254 kWh a year. At a tariff of $0.4659 per kWh that is about $1,050 a year, made up of $954 cooling and $96 heating.
What temperature should I set it to?
- Summer: 25 to 27 degrees
- Winter: 18 to 20 degrees, as the Government’s YourHome guide recommends (YourHome)
Every extra degree increases energy use by roughly 5% to 10% (energy.gov.au). Setting it to 18 in summer will not cool the room any faster. It will just cost more. More ways to cut running costs
Does dry mode save money?
Dry mode uses less energy than full cooling, so it costs less to run. But it is not a dehumidifier, and its ability to reduce humidity is limited. It is useful on a muggy day that is not especially hot.
When is the best time to buy an air conditioner?
Out of season. Demand and lead times peak in the first hot weeks of summer. Quotes are often better, and installers more available, in autumn and spring. More ways to bring the price down
Are there rebates for air conditioning?
In several states, yes, usually for efficient reverse cycle systems and most generously when you are replacing gas heating. An accredited provider normally applies them as an upfront discount in your quote, so you do not claim them back afterwards.
Victoria, New South Wales, South Australia and the ACT all run schemes. See what applies in your state
Can I put an air conditioner in a rental?
A fitted system changes the property, so if you rent, talk to your landlord first. A portable air conditioner needs no installation, and a window unit can come out when you leave, if your landlord agrees.
In Victoria, from 1 Mar 2027, a broken heater in a rental that cannot be repaired must be replaced with an efficient reverse cycle air conditioner, and rentals must have efficient cooling in the main living area at the start of a new lease. Victoria’s discount covers rental properties. Victoria’s scheme
Installation
Do I have to use a licensed installer?
Yes. Anyone who installs, services, repairs or decommissions equipment containing fluorocarbon refrigerant must hold a Refrigerant Handling Licence issued by the Australian Refrigeration Council. Handling refrigerant without one is an offence. A licensed electrician must do the electrical work.
The exception is a pre-charged, plug-in portable air conditioner, where the refrigerant circuit is sealed at the factory.
You can check a licence or a business at lookforthetick.com.au.
How do I check an installer is licensed?
Refrigerant handling in Australia is licensed under a national scheme administered by the Australian Refrigeration Council on behalf of the Australian Government, in place since 2003. Every technician who installs or services a refrigerated air conditioner must hold a current Refrigerant Handling Licence, and the business must hold a Refrigerant Trading Authorisation.
You can look up any technician or business on the public register at lookforthetick.com.au, or ask to see the licence card, which shows what work they are permitted to do.
Using a licensed technician protects the environment, keeps your warranty valid, and means the work is done to the required standard.
Where should the units go?
Indoor unit High on the wall and reasonably central to the room, so air circulates evenly. Somewhere you can reach to clean the filters. Not blowing directly at a bed or a desk if you can avoid it.
Outdoor unit Typically on an external wall near the room being conditioned, with clearance around it for airflow, out of direct afternoon sun where possible, and positioned so its noise does not carry into a bedroom or over a neighbour’s fence. Most councils have night-time noise limits for air conditioner condensers. Your installer should confirm compliance.
Can I put a cover over the outdoor unit to hide it?
Not a solid one. The outdoor unit needs clear airflow to work. Boxing it in makes it work harder, raises running costs and can cause faults.
If the appearance bothers you, ask your installer about screening that maintains the required clearances.
How long does installation take?
A single split system is usually a one-day job. A multi-split takes longer. A ducted system typically takes several days.
Maintenance and repairs
What maintenance do I need to do?
Clean the filters. That is the main one, and it matters more than people expect: a blocked filter restricts airflow, which cuts capacity and raises running costs.
Clean them every two to four weeks during heavy use, and at least at the start of each season. Also keep the outdoor unit clear of leaves and plant growth.
How do I clean the filters?
Check your manual, but the usual process is: open the front panel, slide out the filters, vacuum off loose dust, wash in lukewarm water with a mild detergent, and let them dry fully in the shade before refitting. Do not dry them in direct sun or with a hairdryer.
How often should it be professionally serviced?
Most manufacturers and installers recommend an annual service for a residential system, ideally before the season you use it most. Some warranties require documented servicing, so check your warranty terms.
Ask your installer what an annual service costs before you buy, because it is an ongoing cost that varies.
When will I need to replace my air conditioner?
A well-maintained system commonly lasts ten to fifteen years or more, depending on type, usage and maintenance.
Signs it may be time:
- It runs but no longer reaches the set temperature
- Airflow has dropped noticeably, even with clean filters
- Water leaking inside, or ice on the pipework
- New rattles, grinding or screeching
- Odd or musty smells
- Repeated repairs, or a repair quote that is a large fraction of a new system
- It uses R22 refrigerant, which has been phased out and is expensive to source
- A jump in your power bill with no change in how you use it
Can I remove my old air conditioner myself?
No. There is almost always refrigerant left in the system, and releasing it is an offence as well as a significant greenhouse emission. A licensed technician must recover the refrigerant.
If you are getting a new system, ask whether the quote includes removing and disposing of the old one.
Technical terms
What does EER mean?
Energy Efficiency Ratio: cooling output divided by electrical input at a single test condition. In Australia both are in watts, so an EER of 3.5 means 3.5 units of cooling per unit of electricity. Note that the United States calculates EER differently, so American figures are not comparable.
What is an inverter?
An inverter varies the compressor speed instead of switching it on and off. That means lower running costs, steadier temperatures, quieter operation and better dehumidification. Nearly all split and ducted systems sold in Australia today are inverter models.
What is MEPS?
Minimum Energy Performance Standards: the minimum efficiency a product must meet to be legally sold in Australia, under the Greenhouse and Energy Minimum Standards scheme. It is a floor, not a target. The energy label is what separates a good model from a barely compliant one.
What refrigerant do modern air conditioners use?
Most new split systems sold in Australia use R32. It does not deplete the ozone layer and has roughly one third the global warming potential of R410A, the refrigerant it largely replaced. Neither R32 nor R410A harms the ozone layer. R22, the older refrigerant that did, has been phased out.
About our service
What does Aircon Market cost?
Nothing. Our service is free to you.
How does it work?
Tell us what you need, and we pass your details to up to three independent installers who cover your area. They contact you directly, by phone, SMS or email, usually within 48 hours. You compare their quotes and choose, or choose none of them.
Am I obliged to buy?
No. There is no obligation at any point.