AC Repair vs. Replacement: How to Decide
A dead AC in July forces a fast, expensive decision. Here’s the simple rule for repair vs. replace, plus real 2026 costs so you don’t overpay under pressure.
Updated July 10, 2026 · 7 min read
Air conditioners have a habit of failing on the hottest day of the year, when you’re least inclined to shop carefully. That pressure is exactly how people get talked into a A$15,500 system they didn’t need — or keep pouring money into a unit that should be replaced.
This guide gives you a clear framework for repair vs. replacement, the 2026 costs for each, and the questions to ask before you commit.
The simple decision rule
A widely used rule of thumb: multiply the repair cost by the unit’s age in years. If that number exceeds about A$7,800 replacement is usually the smarter move. A A$620 repair on a 5-year-old unit (A$3,100) → repair. A A$1,100 repair on a 12-year-old unit (A$13,000) → replace.
Also lean toward replacement if the system uses the old R-22 refrigerant (expensive and being phased out), fails repeatedly, or is over ~12–15 years old.
2026 repair costs
Common AC repairs and typical price ranges:
- Capacitor or contactor replacement: A$230–A$700.
- Refrigerant recharge (and leak fix): A$470–A$1,900 depending on refrigerant.
- Fan motor: A$620–A$1,400.
- Compressor replacement: A$2,300–A$4,700 (often the "just replace it" moment on an older unit).
2026 replacement costs
A new system is priced by size (tons) and efficiency (SEER2 rating):
- Central AC unit only: A$7,000–A$12,500 installed.
- AC + furnace (full system): A$12,500–A$21,500 installed.
- Heat pump (heating + cooling): A$9,300–A$25,000 installed, often incentive-eligible.
- High-efficiency units cost more upfront but cut summer bills and may qualify for rebates.
Before you sign
Get a couple of quotes even in an emergency, and make sure the installer does a proper load calculation (Manual J) rather than just matching your old unit’s size — an oversized system short-cycles, wastes energy, and wears out faster. Confirm the quote includes a new thermostat, proper refrigerant line handling, permits, and a labour warranty separate from the manufacturer’s parts warranty.
Heating & cooling costs in Australia
Figures are in Australian dollars, and Australian systems differ from the US. Forced-air "furnaces" are uncommon here — for heating, most homes use reverse-cycle (heat-pump) split or ducted systems, with ducted gas heating common in colder states like Victoria; for cooling, reverse-cycle split systems and ducted units dominate. Refrigerant work must be done by a licensed, ARC-certified technician, and gas work by a licensed gasfitter.
Size the system to the room and climate zone: in the tropical north, humidity and heat load push you toward higher-capacity ducted or multi-split systems, while southern states weight the choice toward heating performance. State rebates apply to efficient systems in some markets.
HVAC System Replacement cost by city
See location-adjusted hvac system replacement costs for your area:
Frequently asked questions
How long should an AC last?
Most central air conditioners last 12–17 years with maintenance. Past that, efficiency drops and parts get harder to find, so replacement often makes sense even if it still runs.
Is a heat pump worth it over a regular AC?
In many climates, yes — a heat pump both cools and heats efficiently, can replace a separate furnace, and frequently qualifies for 2026 rebates and tax credits. Ask an installer to compare lifetime costs for your home.
Why is my AC freezing up?
Usually low refrigerant (a leak) or restricted airflow from a dirty filter or coil. Turn it off to thaw and call a tech — running a frozen unit can damage the compressor.
Can I replace just the outdoor unit?
It’s possible but often unwise — mismatching a new outdoor condenser with an old indoor coil hurts efficiency and can void warranties. A tech should confirm compatibility.
Need a hvac pro?
Describe your job in plain words and get matched with a vetted local pro — free, in seconds. No account needed.