What size air conditioner do I need?

Your air conditioning system needs to be the right size for your home. A system that's too small or too large will waste energy and won't maintain comfortable temperatures so efficiently. Our technicians will calculate the perfect size and capacity for your needs, based on factors such as:

  • the size of your house 
  • the number of cooling zones 
  • the height of your ceilings
  • the number of windows
  • how well-insulated your home is
  • your local climate

The cost of installing air conditioning depends on the type and size of system you choose, its energy output, and how complex the installation is. Split systems are generally cheaper to install than ducted systems. Maxim Air technicians will calculate the cost of your installation and give you an obligation-free quote.

Like every investment in your home, you get what you pay for with air conditioning. The big brands like Daikin, Samsung and Mitsubishi Electric may be more expensive, but you'll benefit from more reliable performance and a wider range of features. Buying an energy-efficient air conditioner from an established brand also means you'll save money on your energy bills.

Ducted air conditioning is the most discreet and least noticeable type of air conditioning. It's also very energy-efficient, especially for medium to large homes.

Cool air flows into your rooms through a system of ducts in your walls, ceilings or floors, connected to a single outdoor unit.

Split systems are the most common type of air conditioning used in Australian homes. Each system comprises an indoor unit and a separate outdoor unit, connected by refrigerant lines rather than ducts.

Multi-head split systems connect multiple indoor 'heads' to a single outdoor unit, which saves space outside your home.

Inverter technology makes air conditioning more energy-efficient, saving energy and delivering more precise cooling.

In VRF systems, an inverter continually adjusts the speed of the compressor motor to regulate temperatures more efficiently.

Energy Efficiency Ratios (EER) are a way to measure the efficiency of cooling systems. They offer a more reliable and precise comparison than energy star ratings.

The ratio is calculated by dividing the output (capacity) of a system by the power it uses. A higher EER means more energy-efficient air conditioning.

In VRF systems, an inverter continually adjusts the speed of the compressor motor to regulate temperatures more efficiently.

If your home gets cold in the winter, reverse cycle air conditioners can switch between heating and cooling whenever you need them to. These systems are more energy-efficient than conventional gas or electric heaters, and when the weather heats up again, they work just like standard air conditioning.

Legionella bacteria may grow in poorly maintained cooling towers, which are primarily used in large commercial air conditioning systems and not in homes.

If you operate one of these systems, regular cooling tower treatments are required by law every six months in New South Wales to prevent the potential spread of Legionnaires' disease.

Regular cleaning of your air conditioner filter to remove dust and dirt helps the system to operate at peak efficiency. We recommend that you clean your filter at least once a month, or more often if you have pets, you live in a dusty area, or someone in your home has allergies.

You should also schedule regular air conditioner maintenance.

Get the answers to common questions about air conditioning in our FAQ. If you have another question, contact Maxim Air’s experts directly on