What Is A Split System Air Conditioner? | Expert Guide 2025

If you’re considering an air conditioning solution for your home or business, you’ve likely come across the term split system aircon. But what is a split system air conditioner, and how does it work? Whether you’re in need of cooling relief during sweltering Australian summers or efficient heating in the winter months, a split system AC unit could be the perfect choice.

In this expert guide, we’ll break down everything you need to know about split system air conditioning units, including their components, how they function, types available, benefits, and factors to consider before installation. We’ll also answer some frequently asked questions and provide maintenance tips to keep your unit running efficiently year-round.

What Is A Split System Air Conditioner?

A split system air conditioner is a type of air conditioning unit that consists of two main components:

An indoor unit, which houses the evaporator coil and blower fan, responsible for circulating cool or warm air inside your space.
An outdoor unit, which contains the compressor and condenser coil, working to release heat outside.

Unlike traditional window air conditioning units, which are housed in a single box, a split AC system is divided into two parts—hence the term “split system.” The indoor unit is typically wall-mounted and connected to the outdoor condenser via refrigerant piping and electrical wiring.

How Does A Split System Air Conditioner Work?

A split system air conditioning unit functions using a refrigeration cycle to either cool or heat your space efficiently. Here’s how it works:

Cooling Mode:
- The indoor unit absorbs heat from the air inside your room using refrigerant.
- The refrigerant carries the heat to the outdoor condenser, where it is released.
- The cooled refrigerant then cycles back to the indoor unit, and the process repeats.
Heating Mode (Reverse Cycle AC):
- The system reverses its operation, extracting heat from the outdoor air and transferring it indoors.
- Even in cold temperatures, the heat pump technology can effectively warm your space.

This process allows reverse cycle split systems to provide both cooling and heating, making them an energy-efficient solution for year-round comfort.

Types of Split System Air Conditioning Units

There are several types of split air conditioning units, each designed for different needs and spaces.

1. Wall-Mounted Split System Air Conditioners

Most common type for homes and small offices.
Mounted high on a wall for even air distribution.
Ideal for bedrooms, living rooms, and small commercial spaces.

2. Multi-Split Air Conditioning System

Connects multiple indoor units to a single outdoor compressor.
Great for cooling or heating multiple rooms independently.
Energy-efficient alternative to installing multiple standalone units.

3. Ducted Split System Air Conditioners

Concealed within ceilings or walls with ducts distributing air throughout the home.
Provides even temperature control across multiple rooms.
A premium solution for whole-home cooling and heating.

4. Floor-Mounted Split System Air Conditioners

Installed near the floor instead of on the wall.
Ideal for rooms with limited wall space or high ceilings.
Great for heating as warm air naturally rises.

5. Ceiling Cassette Split System AC Units

Mounted in the ceiling, distributing air evenly across large areas.
Commonly used in offices, retail stores, and restaurants.

Benefits of a Split System Air Conditioner

Investing in a split air conditioning system comes with numerous advantages:

✔ Energy Efficiency – Uses inverter technology to adjust cooling and heating output based on room temperature needs.

✔ Quiet Operation – Indoor units are designed to operate quietly, making them perfect for bedrooms and living areas.

✔ Easy Installation – Requires minimal structural modifications compared to ducted systems.

✔ Cost-Effective – Lower running costs due to efficient cooling and heating cycles.

✔ Zoning Control – Multi-split systems allow different rooms to be set at different temperatures.

✔ Aesthetic Appeal – Modern, sleek designs blend seamlessly into any home décor.

Factors to Consider When Choosing a Split System Aircon

Before purchasing a split system air conditioning unit, consider the following:

1. Room Size & Aircon Capacity

Choose the right BTU (British Thermal Unit) capacity for your room size.
Small rooms (up to 20m²): 2.5kW split system
Medium rooms (20m² – 40m²): 3.5kW – 5kW
Large spaces (40m²+): 5kW+ or multiple units

2. Energy Efficiency Rating

Look for models with high star ratings to save on electricity bills.
Inverter technology enhances efficiency by adjusting compressor speed.

3. Noise Levels

If installing in a bedroom, opt for a quiet split system air conditioner with a low decibel rating.

4. Installation & Placement

The outdoor condenser should be placed in a well-ventilated area.
Avoid installing the indoor unit near heat sources or in direct sunlight.

5. Additional Features

Wi-Fi Control – Manage your AC remotely via an app.
Air Purification Filters – Removes dust, allergens, and bacteria.
Dehumidification Mode – Reduces indoor humidity levels.

Split System Air Conditioner FAQs

How to Clean an Aircon Filter?

Turn off the AC unit.
Remove the front panel and take out the air filter.
Wash with warm water and mild detergent.
Let it dry completely before reinstalling.

What Size Aircon Do I Need?

The right split system AC unit depends on room size, insulation, and climate.
Refer to a BTU/kW calculator or consult a professional for sizing recommendations.

Why Is My Aircon Dripping Water?

Possible reasons include:
- Blocked drain pipe
- Dirty air filters
- Low refrigerant levels
Regular maintenance can prevent this issue.

How Much to Regas a Car Aircon?

The cost varies but typically ranges between $100 – $300 AUD, depending on refrigerant type and labor costs.

How Much for Ducted Aircon?

Ducted air conditioning systems start from $5,000 – $10,000 AUD, including installation, depending on home size and brand.

Final Thoughts: Is a Split System Air Conditioner Right for You?

If you’re looking for an efficient, cost-effective, and versatile air conditioning solution, a split system aircon is an excellent choice. Whether you need cooling in the summer, heating in the winter, or year-round comfort, reverse cycle split systems offer outstanding performance.

For expert split system air conditioner installation in Australia, contact Alter Electrical today. Our team provides professional advice, installation, and maintenance services to keep your home or business comfortable all year round.

Ready to Install a Split System Air Conditioner?

Get a free quote today from our experts and enjoy energy-efficient heating and cooling tailored to your needs!