Multi-Split Air Conditioning

How Multi-Split Systems Work

A multi-split connects two to five indoor heads (wall-mounted, floor consoles, or slim ducted units) to one outdoor unit. Each room gets independent temperature control and only runs when you want it to — unlike ducted, you're not conditioning the whole house to cool one bedroom.

• 2-room combos: commonly a 5–6 kW outdoor unit running e.g. 2.5 kW + 2.5 kW heads
• 3–4 room combos: 8–10 kW outdoor units running mixed head sizes (e.g. 3.5 + 2.5 + 2.5 kW)
• 5-room combos: 10–14 kW outdoor capacity for larger homes

Note the outdoor unit is usually rated below the sum of the heads — by design, since you rarely run every room at maximum simultaneously.

Multi-Split vs Ducted: Which Way to Go?

Choose multi-split when: you're in an apartment or two-storey home without roof space, you want per-room control and per-room running costs, or you're conditioning 2–4 rooms rather than the whole home. Choose ducted when: you want whole-home coverage with invisible vents, you have accessible roof space, and zoning a single system suits how you live. Multi-splits are also often the smarter retrofit — no ceiling works required.

Multi-Split Rebates

Multi-head systems are squarely inside the rebate schemes. In Victoria, replacing ducted gas heating with a multi-head split system is one of the highest-paying VEU activities — discounts can run into the thousands, with a $1,000 co-payment applying to multi-head installs. NSW ESS and SA REPS both cover qualifying high-efficiency multi-split configurations through accredited providers.