Whole-home comfort
Replacing your ducted air conditioning
At a glance
Replacing an older ducted system starts with the whole home: equipment, ducts and the rooms you use. An assessment establishes what can stay, what needs upgrading and how the new system should be controlled.
Your replacement, in three steps
- 01
Assess
Existing system + home layout
- 02
Design
Equipment + ducts + zones
- 03
Replace
Install + test + explain controls
01 / Check what can stay
Existing ducts are not automatically suitable for a new unit. Their condition, sizing and the new system's requirements need checking. Moving from gas ducted heating to reverse-cycle air conditioning may require upgraded ductwork.
Ask the installer to identify which components are being retained and why. Include outlets, return air, controls and the outdoor location in that discussion. A quote should make the replacement scope clear.
02 / Plan around the whole home
Ducted air conditioning distributes conditioned air through concealed ducts to outlets around your home. A zoned design can control which areas are served, subject to the equipment and airflow requirements.
Mark the rooms used during the day and overnight. Ask how the proposed controls work when fewer areas need heating or cooling, and which zones must remain open. Confirm the layout before installation.
03 / Compare the complete job
Request equipment, ductwork, electrical work, removal and commissioning as separate quote items. Include warranty support and any confirmed incentive. Check whether a site assessment could change the price.
For running-cost comparisons, use your electricity tariff and realistic operating assumptions. A newer system does not guarantee a particular bill saving. Ask the installer to explain the proposed capacity and the reasons behind it.
Save this checklist
Your assessment checklist
- Existing model and repair history
- Floor plan and rooms used together
- Ductwork and access assessment
- Itemised quote and controls demonstration
Common questions
Can my existing ducts be reused?
Only after their condition and suitability for the new equipment are assessed. Ductwork upgrades may be needed, especially when replacing gas heating.
Do I need the same capacity as my old system?
Do not assume so. The replacement should be selected for your current home, coverage and heating and cooling needs.
Sources & editorial notes
Prepared by the SG Aircon team. Published and updated 22 September 2026.
General planning guidance. Equipment, site conditions and any incentive must be checked for your property.
Put your plan into action
Ready to replace your older system?
Send your suburb and existing system details. We will discuss a whole-home assessment.
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