Air conditioning installation costs between $1,000 to $8,000. The final cost depends on the type of system, size of the house, and complexity of the job.
The biggest price difference comes from whether you choose a split system or ducted air conditioning unit. Costs also increase as the number of bedrooms increases, since larger homes need higher-capacity air conditioning systems.
This blog will discuss the costs of split vs ducted air conditioners, costs by home size, costs by unit size and brand, and more.
Split System Vs Ducted Aircon: Which is Cheaper to Install?
Split system air conditioners are cheaper to install than ducted systems. A standard split system unit costs between $1,000 to $2,000, while a ducted air conditioning installation can cost up to $8,000. The key difference in split system vs ducted aircon installation is scale and complexity.
Split air conditioning systems suit smaller homes or single rooms because installation is quick and requires less ductwork. They are popular for apartments, townhouses, and 2- to 3-bedroom homes where targeted cooling is enough.
Ducted air conditioning systems cover the entire property with concealed ducts, which makes them more expensive to install. They are best suited for larger homes with 4 or more bedrooms where full-house cooling is required.
Air Conditioning Cost by Home Size
The table below shows the average installation costs for different home sizes in Melbourne:
Here are the main differences between safety switches and circuit breakers:
| Home Size | System Type | Average Cost Range |
|---|---|---|
| 1 Bedroom Home | RCDs trip when current leaks to earth | Circuit breakers trip when too much current flows through a circuit |
| How fast do they trip? | RCDs respond to faults within 30 milliseconds | Circuit breakers trip in milliseconds to seconds depending on the fault type and breaker rating |
| What do they protect? | RCDs protect people from electrocution | Circuit breakers protect cables, switchboards, and appliances from overheating |
Legal Residential Requirement
Australian wiring rules (AS/NZS 3000) require RCDs on all final sub-circuits in new homes. This applies to lighting, socket outlets, and appliances.
Older homes built before these regulations may have no safety switches at all. Upgrading these boards is strongly recommended for safety and insurance compliance.
RCDs In Switchboards
RCDs are usually installed on each individual circuit within the switchboard. This allows one fault to isolate safely without shutting off the entire board.
Each RCD monitors the difference in current between active and neutral conductors. If that current leaks to earth — such as through a human — the RCD trips within 30 milliseconds.
Circuit breakers protect wiring, not people. They trip when electrical flow exceeds the cable’s safe limit or a short circuit occurs.
Unlike RCDs, they don’t detect current leakage. Their role is to prevent overheating, arcing, and fires caused by excess current.
How Circuit Breakers Detect Faults
Circuit breakers measure the amount of current flowing through a circuit. When that current exceeds its rating, the breaker trips.
This protects the cable and connected appliances from heat damage. It does not prevent electrocution if someone touches live wires.
Types Of Circuit Breakers: Single‑Phase Vs Double‑Pole
Single-phase circuit breakers are used on general lighting and power circuits. They handle 240 V loads like GPOs and lights.
Double-pole circuit breakers are designed for higher-demand appliances such as cooktops, air conditioners, and electric hot water units. These protect both active and neutral lines simultaneously.
Is A Safety Switch And An RCD The Same Thing?
Yes — a “safety switch” is the everyday name, and “RCD” is the technical term. Both refer to the exact same device.
Government regulations, wiring rules, and electrical retailers often use “RCD,” while consumer material prefers “safety switch.” Search engines show people use both terms interchangeably, so it’s important to reference both.
Key Differences Between Safety Switches (RCDs) And Circuit Breakers
When To Use Both Device
Every home and business should have both RCDs and circuit breakers. They work together to provide complete circuit protection.
Some switchboards combine both into a single device called an RCBO, but others use them separately depending on layout, load types, and compliance requirements.
Combined RCD/Circuit Breaker Units
Combination units are called RCBOs or Residual Current Breaker with Overcurrent protection. These do the job of both a circuit breaker and a safety switch.
They’re ideal when space is limited or when separate RCDs and breakers aren’t practical. Many modern boards now use only RCBOs across all circuits.
Why You Should Test RCDs Regularly
RCDs must be tested every 3 months using the test button marked “T” or “Test.” This simulates a fault and checks that the RCD trips correctly.
If it fails to trip, the switch no longer protects you. It must be replaced immediately by a licensed electrician.
Routine testing ensures your RCD will work during an emergency. It takes seconds to check and could save a life.
