Air conditioning buyer guide: choosing, costing and looking after your system

Split vs multi-split vs ducted

• Split system — one indoor unit and one outdoor unit. Suits a single room or open-plan area; usually the simplest and lowest-cost install, and each unit runs independently.
• Multi-split — several indoor units on one outdoor unit. Suits two to five rooms where outdoor space is limited; each room has its own controller, but all indoor units depend on the one outdoor unit.
• Ducted — a concealed indoor unit in the roof or under the floor with ducts and vents to each room. Suits whole-home or larger-area comfort with minimal visible equipment; needs adequate roof space and is the most involved install.
• Cassette and under-ceiling units — common in shops, offices and clinics where wall space is limited or air needs to spread across a larger room.

What affects the cost of an installation

• System type and capacity, sized to the room or home rather than guessed.
• Distance and route between indoor and outdoor units, and whether pipework can be concealed.
• Wall construction, roof access and working height (two-storey and tight roof spaces take longer).
• Electrical supply — whether a dedicated circuit, isolator or switchboard work is needed.
• Condensate drainage route and outdoor unit mounting (ground, wall bracket or roof).
• Removal and disposal of existing equipment, including refrigerant recovery.
• For ducted systems: number of outlets, zones, return air position and controller choice.

Reading a quote: inclusions and exclusions to check

• Make, model and capacity of every indoor and outdoor unit.
• Pipe run length allowed for, and the rate for anything beyond it.
• Electrical work included, and what is excluded (for example switchboard upgrades).
• Removal of old equipment and making good of wall penetrations.
• Commissioning, controller setup and a handover walkthrough.
• Manufacturer warranty terms as provided with the equipment.
• Common exclusions to ask about: patching and painting, asbestos, structural or roof alterations, and after-hours access.

Repair or replace?

A repair usually makes sense when the system is relatively young, the fault is a single component, and it has otherwise performed well. Replacement is worth pricing alongside a repair when the system is older, needs a major component such as a compressor, has repeated faults, uses a phased-out refrigerant, or no longer keeps the space comfortable. We'll explain the fault and give you the options so you can decide.

Zoning, smart controls and running costs

• Zoning lets a ducted system condition only the rooms in use, which can reduce running time.
• Wi-Fi and smart controllers allow scheduling and remote on/off where the equipment supports it.
• Running costs depend on system size and efficiency, insulation, sun exposure, thermostat setting, hours of use and your electricity tariff — so we don't quote a single running-cost figure.
• Correct sizing matters: an undersized system runs flat out, an oversized one cycles on and off and controls humidity poorly.
• Setting cooling a few degrees warmer, closing doors to unused rooms and keeping filters clean all help.

Installation, commissioning and handover

• Site assessment where the job needs one, confirming unit positions, pipe route and electrical requirements.
• Installation with regulated electrical and refrigerant work undertaken by appropriately licensed trades.
• Commissioning: pressure testing, evacuation, refrigerant checks and confirming the system heats and cools correctly.
• Handover: how to use the controller and modes, filter cleaning, and the manufacturer warranty information.

Aftercare and servicing

Clean wall-split filters regularly during heavy use, keep outdoor units clear and rinse salt build-up on coastal properties. Most homes benefit from an annual service before summer; commercial sites running long hours usually need more frequent maintenance. Book a service any time, including for systems we didn't install.