What Is a Split System Air Conditioner? | Brisbane Guide
How Split Systems Work, What They Cost and Whether One Is Right for Your Home
A split system air conditioner is the most popular type of AC in Australian homes. It consists of two units — an indoor unit mounted on the wall and an outdoor compressor unit — connected by refrigerant piping and electrical cabling. For homeowners across North Lakes, Redcliffe, Mango Hill, Chermside and Aspley, here is everything you need to know about split system air conditioning.
How Does a Split System Work?
- The indoor unit draws warm air from the room across a cold evaporator coil
- Refrigerant in the coil absorbs the heat from the air
- The cooled air is blown back into the room
- The heated refrigerant travels through piping to the outdoor unit
- The outdoor compressor releases the heat outside
- The cooled refrigerant cycles back to the indoor unit
Reverse cycle split systems can also heat by reversing this process — absorbing heat from outdoor air and releasing it inside.
Split System Sizes and What They Cool
| System Size | Room Size | Typical Use |
|---|---|---|
| 2.5kW | Up to 20m² | Small bedroom, study |
| 3.5kW | 20 – 35m² | Standard bedroom, small living room |
| 5.0kW | 35 – 50m² | Large bedroom, medium living room |
| 7.0kW | 50 – 65m² | Large living room, open plan area |
| 8.0 – 9.5kW | 65 – 80m² | Large open plan, combined living/dining |
Getting the right size is critical. An undersized system runs constantly and never reaches temperature. An oversized system short-cycles, wasting energy and wearing out faster. A licensed electrician or AC installer can calculate the correct size based on room dimensions, insulation, window orientation and ceiling height.
Split System Installation Costs in Brisbane
| System Size | Supply + Install (AUD) |
|---|---|
| 2.5kW | $1,500 – $2,500 |
| 3.5kW | $1,800 – $3,000 |
| 5.0kW | $2,200 – $3,800 |
| 7.0kW | $2,800 – $4,500 |
| 8.0 – 9.5kW | $3,500 – $5,500 |
| Electrical circuit + isolator | $250 – $500 |
| Switchboard upgrade (if needed) | $800 – $3,500 |
Electrical Requirements for Split System Installation
Every split system air conditioning installation requires:
- A dedicated electrical circuit from the switchboard
- An isolator switch near the outdoor unit
- Correct cable sizing for the system's power draw
- Safety switch (RCD) protection on the AC circuit
- Surge protection to protect the compressor from power surges
If your switchboard is full or uses old ceramic fuses, a switchboard upgrade may be needed before the AC can be installed.
Advantages of Split Systems
- Lower cost than ducted systems
- Quick installation (usually half a day to one day)
- Energy efficient (modern inverter models)
- Quiet operation
- Reverse cycle heating and cooling
- Individual room control
- Wide range of sizes available
Reduce Running Costs with Ceiling Fans
Using ceiling fans alongside your split system creates a wind-chill effect that lets you raise the thermostat 2-3 degrees while maintaining comfort. This reduces AC running costs by 20 to 30 percent. Ceiling fans cost just 2-3 cents per hour to run.
Areas We Service Across Brisbane and North Brisbane
Connex Electrical provides expert electrical services across Brisbane and North Brisbane, including:
- North Lakes
- Redcliffe
- Mango Hill
- Griffin
- Kallangur
- Burpengary
- Morayfield
- Caboolture
- Chermside
- Aspley
- Everton Park
- Stafford
- Wavell Heights
- Murrumba Downs
- Rothwell
- Deception Bay
- Petrie
- Lawnton
- Strathpine
- Brendale
- Albany Creek
- Eatons Hill
- Warner
Our Full Range of Electrical Services
- Switchboard Upgrades
- Emergency Electrician
- Air Conditioning Installation
- Electrical Safety Inspections
- Surge Protection
- EV Charger Installation
- LED Lighting Installation
- Ceiling Fan Installation
- Smoke Alarm Installation
- Powerpoint Installation
- Residential Electrician
- Commercial Electrician
- Data Cabling
Need a Split System Installed?
Connex Electrical handles the full electrical side of split system installation — dedicated circuits, isolator switches, switchboard upgrades and surge protection.
Call 0474 207 609 or visit our contact page to book.
Frequently Asked Questions
What is a split system air conditioner?
A split system has an indoor wall-mounted unit and an outdoor compressor unit connected by refrigerant piping. It cools (and heats, if reverse cycle) individual rooms.
How much does a split system cost to install in Brisbane?
Most split system installations cost $1,800 to $5,500 depending on the size and complexity of the installation.
Do I need an electrician for split system installation?
Yes. A dedicated electrical circuit, isolator switch and potentially a switchboard upgrade are required for every split system installation.
What size split system do I need?
System size depends on room dimensions, insulation, window orientation and ceiling height. A 5kW system suits most standard living rooms.
How long does a split system last?
A well-maintained split system typically lasts 15 to 20 years. Regular filter cleaning and annual servicing extend lifespan.
Need this done in your suburb? Connex Electrical services all North Brisbane and Moreton Bay suburbs including Carseldine · Lawnton · Woody Point.
Learn more about our Air Conditioning Installation services → | All suburbs we service
Call 0474 207 609 for a free quote.
Our Electrical Services
Air Conditioning Installation · Ceiling Fan Installation · Switchboard Upgrades · Smoke Alarm Installation · Powerpoint Installation · LED Lighting Installation · Electrical Maintenance · Electrical Safety Inspections · EV Charger Installation · Emergency Electrician · Commercial Electrician · Data Cabling · Surge Protection
Areas We Service
Electrician North Lakes · Electrician Redcliffe · Electrician Chermside · Electrician Caboolture · Electrician Morayfield · Electrician Burpengary · Electrician Narangba · Electrician Kallangur · Electrician Mango Hill · Electrician Griffin · Electrician Dakabin · Electrician Petrie · Electrician Lawnton · Electrician Deception Bay · Electrician Rothwell · Electrician Kippa-Ring · Electrician Margate · Electrician Clontarf · Electrician Scarborough · Electrician Woody Point · Electrician Bridgeman Downs · Electrician Murrumba Downs · Electrician Aspley
Industry Resources
- QBCC — Queensland Building and Construction Commission
- Energex — SE Queensland Electricity
- Electrical Safety Office Queensland
Need an electrician? Call Connex Electrical on 0474 207 609 for a free quote.