Choosing the right air con isn’t just about cooling your home — it’s about comfort, energy use and long-term costs. A split system is one of the most popular choices in Australia, and understanding how it works (plus what it costs to run and install) can save you hundreds each year.
How a Split System Works
A split system air conditioner has two main parts:
- Indoor unit – mounted on your wall, it blows cooled or heated air into your room.
- Outdoor unit – houses the compressor and condenser, releasing heat outside.
The two are connected by pipes filled with refrigerant, which transfers heat between indoors and outdoors. When cooling, heat is absorbed from inside and pushed outside. When heating (with reverse cycle), the process flips.
Looking for models? Lucky we've got heaps: browse our range of split system air conditioners.
What Is a Reverse Cycle Air Conditioner?
A reverse cycle air conditioner is simply a split system that can both cool and heat. In summer, it removes heat from indoors. In winter, it pulls warmth from the outside air (even in cold conditions) and brings it in.
This makes reverse cycle units one of the most cost-effective heating options for Australian homes compared to gas or portable heaters.
Cooling-only vs Reverse Cycle
|
Feature |
Cooling-Only Split System |
Reverse Cycle Split System |
|
Functions |
Cooling only |
Cooling + heating |
|
Year-round use |
No |
Yes |
|
Initial cost |
Lower |
Slightly higher |
|
Best for |
Hot regions only |
All Australian climates |
How Much Electricity Does an Air Conditioner Use?
Air conditioners are rated in kilowatt hours (kWh), which shows how much energy they use per hour.
Formula to estimate energy usage:
Power input (kW) × Hours used = kWh per day
Example:
A 2.5 kW split system with 0.7 kW input running for 6 hours = 4.2 kWh per day.
Using AEMO’s average rate of $0.31 per kWh, this costs about $1.30 per day.
Running Cost Comparison (approx.)
|
Unit size |
Fan speed |
Temp setting |
Power use per hour |
Cost per hour |
|
2.5 kW |
Low |
24°C |
0.5 kWh |
$0.16 |
|
2.5 kW |
High |
18°C |
0.9 kWh |
$0.28 |
|
7 kW |
Medium |
22°C |
2.0 kWh |
$0.62 |
|
7 kW |
High |
18°C |
2.5 kWh |
$0.78 |
Rule of thumb: A small bedroom unit will usually cost 20–30 cents per hour, while a big living room unit could be 60–80 cents per hour at full power.
Choosing the Right Unit for Your Room Size & Climate Zone
Getting the right size is key. Too small and it will struggle, too big and you’ll waste money.
Room size guide:
- Up to 20 m² (bedroom, study) → 2–2.5 kW
- 20–40 m² (living room) → 3.5–5 kW
- 40–60 m² (open-plan) → 6–7 kW
For smaller spaces, check out our portable air conditioners.
Check the ZERL (Zoned Energy Rating Label):
Every new split system comes with a label that shows energy efficiency in three Australian climate zones:
-
Hot (e.g. QLD, NT): Focus on the cooling stars — more stars = cheaper to run in
the tropics. - Average (e.g. Sydney, Adelaide, Perth): Balance of cooling and heating stars matters most.
- Cold (e.g. TAS, southern VIC): Look at heating stars — that’s where the savings stack up.
Tip: A unit with strong heating stars in the Cold zone might cost a little more upfront but will save significantly on winter bills in cooler climates.
Split System Installation Types & Costs
Install type can change what you’ll pay by hundreds of dollars. Here are the main options, note that your costs will vary by type and location and for an exact cost you'll need to be quoted by a qualified electrician.
|
Installation Type |
What it Means |
When You’ll Likely Need It |
Typical Inclusions & Extra Costs (AU) |
|
Back-to-Back |
Indoor head on an external wall, outdoor unit directly behind it outside. |
Single-storey homes with easy outdoor access. |
Standard install: ~3 m of pipe, drain and trunking. Base cost around $600–$900. |
|
Back-to-Back with Wall Brackets |
Same, but outdoor unit mounted on brackets instead of a slab. |
Where ground space is tight or airflow is blocked. |
Brackets ~$90–$120 plus labour. |
|
Up-and-Over |
Pipes run up through the ceiling and over to another wall or roof. |
Internal-wall installs or upstairs rooms. |
Extra labour and pipe length. Higher than back-to-back. |
|
Side Run |
Pipes run sideways through walls to reach the outdoor unit. |
Apartments or homes with awkward side access. |
Charged per extra metre ($50–$80 typical). |
|
Long Pipe Run |
Line-set distance exceeds 3–4 m. |
Outdoor must sit on a balcony, side passage or distant slab. |
Per-metre charges apply, may reduce efficiency slightly. |
|
Roof or Upper-Level Placement |
Outdoor mounted on roof or upper deck. |
No usable ground space. |
Roof brackets (~$300 each), roof access labour, double-storey surcharge. |
|
Condensate Pump |
Small pump lifts condensate when gravity drain isn’t possible. |
Indoor units on internal walls. |
Pump hardware $200–$300 plus install time. |
Quick guide: Single-storey with an external wall? Expect a back-to-back. Internal wall or upstairs? Budget for up-and-over.
Energy Efficiency Tips to Save on Bills
You can cut costs without sacrificing comfort:
- Set temps wisely – 24–25°C in summer, 18–20°C in winter.
- Use timers and eco modes – stop running units when you’re out.
- Pair with a pedestal fan – helps circulate cool air, so you can set the air con higher.
- Seal gaps – draught-proof doors and windows.
- Maintain filters – clean them every few months for airflow.
- Annual service – keeps efficiency high and reduces strain on the motor.
Example: Raising your summer set temp from 22°C to 25°C can cut cooling costs by around 20%.
Why SEER Matters
When comparing models, check the Seasonal Energy Efficiency Ratio (SEER). This rating shows how efficiently a unit performs across an entire cooling or heating season. The higher the SEER, the less electricity it uses to deliver the same comfort. In short: a unit with a strong SEER may cost a little more upfront but saves you on running costs year after year.
Bi-Rite’s Top Energy-Efficient Air Conditioner Picks
Here are some popular, energy-smart models to consider. Along with efficiency ratings and price ranges, we’ve added real feedback from Aussie households to show how these units perform day to day.
Find these models and more in our full range of air conditioners.
|
Model |
ZERL Ratings by Zone |
Noise Level (Quiet mode) |
Price Range |
|
Panasonic C2.5kW H3.2kW Reverse Cycle Split System and Air Purifier |
Cooling (hot climate): 4.5 Star |
19 dB |
$1,199–$3,299 |
|
Fujitsu C3.5kW / H3.7kW Lifestyle Next Series Split System Airconditioner - Complete Set |
Cooling (hot climate): 4.5 Star |
19 dB |
$1,199–$3,299 |
|
Hisense 3.7kW / 3.9kW U Series Reverse Cycle Split System Airconditioner |
Cooling (hot climate): 7.5 Star |
19 dB |
$999–$2,399 |
|
Mitsubishi Electric 3.5kW / 3.7kW Split System Airconditioner DRED with Wi-Fi |
Cooling (hot climate): 3.5 Star |
22 dB |
$1,189–$3,099 |
|
Westinghouse 3.6kW / 4.4kW Reverse Cycle Invert Split System Airconditioner |
Cooling (hot climate): 6 Star |
32 dB |
$899–$2,999 |
FAQs: Air Conditioning for Aussie Homes
Is reverse cycle more expensive to run than cooling-only?
No. While reverse cycle costs a little more upfront, it saves on winter heating bills compared to electric or gas heaters.
Can I install a split system myself?
No. Installation must be done by a licensed installer (ARCtick certified in Australia).
What’s the ideal temperature setting for summer/winter?
24–25°C in summer and 18–20°C in winter balance comfort and efficiency.
How long does a split system last?
With regular maintenance, expect 10–15 years.
