What’s the best energy efficient rating for split system air conditioners
If you’re shopping for a split system in Adelaide or Melbourne, you’ve probably noticed the star rating label on the front of every unit in-store. It’s tempting to let price be the deciding factor, but that label matters just as much — it’s a direct indicator of what you’ll actually pay to run the thing over its lifetime.
How the Star Rating System Works
Australia’s Energy Rating Label is mandatory on split systems, along with fridges, washing machines, dryers, TVs and a handful of other appliance categories. For split systems, it compares cooling (and separately, heating) output against energy consumed — more stars means the unit delivers more comfort per watt of electricity. Standard labels display up to 6 stars, but the most efficient current models can show up to 4 additional stars in a “super efficiency” zone, effectively rating up to 10 stars for the very best performers.
One thing worth understanding before you compare labels side by side: units are only rated against others of a similar capacity. A 6-star 2.5kW unit and a 6-star 7.0kW unit aren’t directly interchangeable — the rating tells you how efficient a unit is for its size, not which size to buy in the first place. We cover how to get the sizing right in our split system sizing and efficiency guide — worth reading alongside this one, since size and star rating together determine your real running cost.
What Actually Counts as a Good Rating?
As a general guide, 6 stars or more on the cooling rating is a strong benchmark for most Adelaide and Melbourne homes, where summer cooling tends to drive the bulk of running costs. Units in the super-efficiency zone (above 6 stars) cost more upfront but can meaningfully reduce your bill over the life of the unit — whether that trade-off is worth it depends on how often and how long you’ll run the system. We break down how to weigh that upfront-cost-vs-running-cost decision in our energy efficiency guide, rather than repeating it here.
You can check current ratings directly on the Australian Government’s Energy Rating website before you buy — it’s a useful way to confirm a model’s rating hasn’t changed since a display sticker was printed.
What Else to Check Before You Buy
The star rating is only part of the picture — a highly rated unit still won’t perform well if it’s the wrong fit for the room. Before you decide, it’s worth assessing:
- Room size and ceiling height
- External wall material (brick retains and releases heat differently to timber)
- Insulation quality in the walls, ceiling and floor
- Window glazing type and size
- Available outdoor space for the compressor
- Whether you need permission to install a wall unit (especially in a rental)
- How much low-noise operation matters, particularly for bedrooms
A licensed technician can walk through all of this with you and recommend a genuinely well-matched system, rather than just the highest-rated one on the shelf.
Get Help Choosing an Energy Efficient Split System
The easiest way to land on the right split system is to talk it through with someone who installs them for a living. Rite Price Heating & Cooling offers onsite consultations across Adelaide and Melbourne, and we’ll recommend a system based on your space and budget — not just the easiest sale. For the full picture on reverse cycle split systems, see our ultimate guide.
