Address uncontrolled draughts, curtains, shading and insulation where practical. A lower heating or cooling load can change the size and running pattern you need.
Reduce the load before sizing the system
Comfort depends on the home, climate, rooms and operating pattern as well as the appliance. Start with draughts, insulation and shading, then compare equipment sized for the spaces you will actually use.
Start with the home
Lower demand before buying capacity
Record which rooms need conditioning, their floor area, ceiling height, orientation, glazing and how often they are occupied.
For non-ducted air conditioners, compare the Zoned Energy Rating Label for the hot, average or cold zone that applies to your location.
Compare systems
Separate efficiency from suitability
Reverse-cycle air conditioning
Reverse-cycle systems move heat instead of creating it directly. Government guidance says market models can provide about 3 to 6 units of heating or cooling for each unit of electricity used.
- Compare similar capacities in the correct climate zone
- Check heating performance at low outdoor temperatures
- Record indoor and outdoor noise ratings
- Ask how zoning and part-load operation are controlled
Existing gas or resistive heating
Do not compare appliance fuel prices alone. Include efficiency losses, electrical fan use, fixed gas charges that may remain, room coverage and whether another gas appliance keeps the connection necessary.
- Confirm flue and ventilation safety requirements
- Price any switchboard or electrical work
- Identify rooms that can be conditioned separately
- Model the expected hours and thermostat settings
Written quote checklist
Require enough detail to compare like with like
- Exact indoor and outdoor model numbers
- Rated heating and cooling capacity for each zone
- Zoned Energy Rating Label values for your climate
- Indoor and outdoor sound power information
- Room-by-room sizing assumptions and design temperatures
- Electrical, switchboard, drainage and mounting work
- Ducting, zoning controls and sealing work where applicable
- Equipment, installation and workmanship warranties
Do not size from floor area alone.
A site assessment should consider climate, construction, glazing, orientation, insulation, air leakage, occupancy and room use. Oversizing can add cost and reduce effective part-load operation.
Current support
Check incentives by postcode before signing
Heating and cooling assistance is location and eligibility dependent. Use the Australian Government rebate directory, then confirm the program directly with the administering government or provider before accepting a quote.