Connect multiple indoor units to a single outdoor compressor — giving every room independent climate control without multiple outdoor units cluttering your property.
A multi-split system air conditioner is a refrigerated heating and cooling system that connects two or more indoor units to a single outdoor compressor unit. Unlike a standard split system — which pairs one indoor unit with one dedicated outdoor unit — a multi-split system allows you to install between two and eight indoor units in different rooms or zones across your property, all powered and controlled by one outdoor unit.
Each indoor unit operates completely independently from the others. One room can be cooling while another is heating, and a third can be switched off entirely — all at the same time, from the same outdoor unit. The occupant in each room sets their own preferred temperature, fan speed, and operating mode without affecting any other zone.
The outdoor compressor uses advanced inverter technology to manage and distribute refrigerant to each indoor unit precisely and efficiently, adjusting its output continuously in response to the combined demand across all active zones. Multi-split systems also support a variety of indoor unit types — wall-mounted, ceiling cassette, floor-mounted, and compact ducted — so you can choose the most appropriate installation style for every room.
Homes, apartments, townhouses, and commercial spaces needing air conditioning in multiple rooms
Connect between 2 and 8 indoor units to one outdoor compressor — depends on brand and model
Every indoor unit is fully independent — each room has its own temperature and mode settings
Reverse cycle — efficient heating in winter and cooling in summer across all zones
Provides multi-room coverage without the cost and complexity of a full ducted system
Understanding how your system operates helps you use it efficiently and recognise early signs of a problem.
The outdoor unit contains a variable-speed inverter compressor that monitors real-time demand from every connected indoor unit. It adjusts its speed continuously — not just on or off — delivering precise, energy-efficient output across all zones simultaneously.
Refrigerant is circulated through individual pipe sets to each indoor unit. Each indoor unit has its own expansion valve that controls refrigerant flow independently, allowing one room to be cooling at full capacity while another maintains a steady temperature at minimal load.
In cooling mode, each indoor unit absorbs heat from the room air and transfers it outside via the outdoor condenser. In heating mode, the process reverses — the outdoor unit extracts heat from outside air and delivers it into each active zone, efficiently warming every room.
One of the most valuable advantages of a multi-split system is the ability to mix and match different indoor unit styles on the same outdoor compressor — choosing the best option for each individual room.
The most popular choice for residential rooms. Mounted high on the wall, these units distribute conditioned air horizontally and are available in a wide range of capacities. Easy to install, operate, and maintain.
Most PopularRecessed into the ceiling and distributing air in four directions simultaneously for even, draught-free coverage. Ideal for open-plan living areas, commercial offices, and retail spaces where wall mounting is impractical.
Commercial FavouriteInstalled at floor level — ideal for rooms with floor-to-ceiling windows, sloped ceilings, sunrooms, or heritage properties. Delivers warm air at floor level during heating mode for natural, comfortable warmth.
Renovation FriendlyA slim hidden unit installed inside the ceiling cavity, delivering air through short ducts to ceiling vents with no visible indoor unit at all. Provides the aesthetic of a ducted system without the full ducted installation cost.
Fully ConcealedUnderstanding the key differences helps you make the right choice for your property, budget, and long-term needs.
Multi-split systems offer a unique combination of flexibility, space efficiency, and independent zone control that no other air conditioning type can match.
Connect multiple rooms to a single outdoor compressor — dramatically reducing the visual clutter and outdoor space required compared to installing individual split systems for each room.
Every indoor unit operates independently. One room can be cooling while another heats and a third is switched off — simultaneously, from the same system, with no compromise between zones.
Combine wall units, ceiling cassettes, floor-mounted units, and compact ducted units on the same outdoor compressor — the right solution for every room, regardless of its layout or architecture.
A single, well-positioned outdoor unit dramatically improves your property's exterior appearance — important for homeowners, body corporates, and commercial operators who value a clean, professional look.
The outdoor inverter compressor continuously modulates output to match combined real-time demand, eliminating the energy waste of fixed-speed on-off cycling for lower electricity bills across all zones.
For properties without roof cavity space for a full ducted system, a multi-split provides whole-property coverage without any ductwork — ideal for apartments, townhouses, and heritage buildings.
Selecting the correct outdoor compressor capacity and indoor unit combination requires careful consideration of each room individually. Getting the sizing right is essential for efficient, reliable performance across all zones.
The outdoor unit must have sufficient total capacity to meet the combined demand of all connected indoor units. Our technicians conduct a thorough load calculation for every room, taking into account room size, ceiling height, insulation, window area and orientation, sun exposure, and typical occupancy — then select the configuration that delivers optimal performance and efficiency across all zones.
We also advise on the best outdoor unit location, considering airflow clearance, sun exposure, proximity to indoor units, noise impact on neighbours, and access for future servicing.
Every room assessed individually — size, ceiling height, insulation, windows, and occupancy
Selected to handle combined zone demand without oversizing or undersizing the compressor
Wall, cassette, floor, or ducted — chosen for each room's architecture and requirements
Location assessed for airflow, noise, sun exposure, and easy access for servicing
No cost, no obligation — we design the right system for your property before any commitment
Professional installation is essential for multi-split systems. The complexity of connecting multiple indoor units to one outdoor compressor requires experienced HVAC technicians trained in multi-split architecture.
Complete walk-through of all rooms and the property exterior to plan routes, positions, and outdoor unit location.
Cooling and heating load calculated for every individual zone to determine the correct indoor and outdoor unit capacities.
We select the right outdoor unit, indoor unit type and capacity for each room, and design the refrigerant and electrical layout.
All units supplied at competitive prices across all major brands — matched indoor and outdoor units from the same manufacturer.
All indoor units mounted, outdoor unit installed, individual refrigerant pipe sets run and insulated, drain lines installed.
Licensed electrical connections for the outdoor unit and all indoor units, including communication wiring between units.
Complete refrigerant circuit vacuumed, leak-tested, and charged to the manufacturer's exact specification for every circuit.
All zones tested across all modes and fan speeds. Full user handover — controls, operation, and maintenance explained.
Multi-split systems benefit significantly from annual professional servicing. Our comprehensive service covers every indoor unit and the outdoor compressor — keeping all zones efficient, clean, and reliable.
Multi-Split Brands We Install, Service & Repair
All technicians hold current ARCTICK refrigerant licences, licensed electrical worker certificates, and manufacturer training across all major multi-split brands.
Multi-split diagnosis and repair requires specific expertise beyond standard split system knowledge. Our technicians are trained and experienced in multi-zone system architecture and communication protocols.
We provide a free in-home assessment and system design consultation — advising on the best outdoor unit, indoor unit types, and configuration for your property before any commitment.
Same-day multi-split repair available in most service areas. We carry a comprehensive inventory of replacement parts for all major brands to complete repairs in a single visit.
Every installation and repair is backed by our workmanship guarantee. If our work is at fault, we return and fix it at no additional charge — no arguments, no conditions.
Our emergency repair line is open 24 hours a day, seven days a week. Because a multi-split fault affects all zones, we treat multi-split emergencies with the highest priority.
Everything you need to know about multi-split system air conditioners — installation, configuration, running costs, and more.
It depends on the brand and model of the outdoor unit. Most residential multi-split systems support between two and five indoor units. Larger commercial outdoor units can support up to eight or more. Our technicians will advise on the right configuration for your property.
Generally no. Multi-split systems are designed to work with matched indoor and outdoor units from the same manufacturer. Mixing brands can cause communication errors, inefficient operation, and will typically void both warranties. We always install matched-brand systems.
Modern multi-split systems with inverter compressors are highly efficient and in many cases comparable in running costs to individual inverter split systems. The exact running cost depends on usage patterns, the number of active zones, and the efficiency rating of the system installed.
Because all indoor units share one outdoor compressor, a fault will affect all zones until repaired. This makes annual servicing particularly important for multi-split owners — catching potential issues before they cause a complete system failure.
Yes — the vast majority of multi-split systems available in Australia are reverse cycle, providing efficient cooling in summer and heating in winter across all connected zones. A complete year-round climate control solution for your entire property.
They serve different needs. Ducted provides seamless whole-home coverage through hidden vents and is more appropriate for larger properties. Multi-split is better suited to apartments, townhouses, and properties without roof cavity space — and is generally less expensive to install than a full ducted system.
Free in-home assessment. System design included. All brands. Licensed technicians. Same-day service and 24-hour emergency support available.