If your AC is noisy, underperforming, or costing you more than it should, you might be wondering whether it’s time to replace it.
Here’s the truth: most people wait too long to replace their AC unit. They put up with weak airflow, noisy operation, or rising power bills, hoping it will last just a bit longer.
In this guide, you’ll learn when to replace your AC, what it costs, and what to expect—so you can make a smart decision without the stress.
When to Replace Your AC?
If your system is showing these signs, it might be time to stop repairing and start replacing:
Frequent Breakdowns
If your unit needs constant repairs, it’s not just frustrating. It’s costing you more than it should. After a couple of callouts, you’re likely spending money that would be better put towards a new system.
Rising Energy Bills
Old systems become less efficient over time. If your power bills are climbing but your usage hasn’t changed, your AC might be working harder to deliver the same results and failing to do so efficiently.
Inconsistent Cooling or Poor Airflow
Rooms too hot, too cold, or never quite right? That’s a clear sign your system is struggling. Poor airflow could also point to a serious internal issue that won’t go away with a quick fix.
Your System Is Over 10 to 15 Years Old
Air conditioners aren’t built to last forever. If yours is more than a decade old, it’s likely using outdated technology and costing more to run. Replacing it may actually save you money in the long run.
Strange Noises or Bad Smells
Grinding, rattling, or a burnt smell coming from the vents usually means something is worn out or malfunctioning. Sometimes it’s fixable, but not always worth the cost.
If you’re seeing one or more of these issues, your AC may be nearing the end of its life. Next, we’ll tackle the key question: Should you repair it or replace it?
Repair vs Replace: Which One Makes More Sense?
When your air conditioner starts acting up, the first instinct is often to repair it. A quick fix feels cheaper, faster, and less hassle. But that short-term relief can sometimes lead to long-term regret.
Here’s how to decide which path actually saves you more time and money.
The 50 Per Cent Rule
This is a simple benchmark used by many HVAC professionals. If the cost of repairs is more than 50 percent of the price of a new system, replacement is usually the smarter move. For example, if a major repair costs $2,000 and a new system is around $4,000, you’re better off upgrading.
Age + Repair = Red Flag
If your system is over 10 years old and it needs a major fix, that’s often a sign it’s time to replace. Older units are less energy efficient and more prone to ongoing problems. You could end up throwing good money after bad.
Minor Repairs Can Still Be Worth It
If the issue is small, like a blocked drain, a faulty capacitor, or a thermostat issue, it’s reasonable to go ahead with a repair, especially if the unit is under 10 years old and has been reliable until now.
Think Long-Term Running Costs
Newer systems use far less energy, especially if your current one is a decade old or more. So even if a repair seems cheaper up front, a new unit might pay for itself within a few years through lower electricity bills.
Warranty Matters
If your system is still under warranty, a repair may cost you little to nothing. But once that coverage ends, parts and labour can add up quickly. Check your warranty status before making a decision.
In short, if your system is old and expensive to fix, replacement often makes more sense. But if the issue is minor and the system is otherwise solid, a repair might do the trick.
What’s Involved in an AC System Replacement?
If you’ve never replaced an air conditioner before, it can feel like a big unknown. The good news? A professional installer will handle the heavy lifting, but it still helps to understand what’s happening at each step.
Step 1: Assessment and Quote
First, an installer will visit your home to assess your needs. They’ll look at:
- The size and layout of your home
- Your current system (if any)
- Electrical setup
- Access for installation
From this, they’ll recommend a suitable system and give you a quote that includes supply and installation.
Step 2: Removal of the Old Unit
If you’re replacing an existing system, the old unit needs to be removed. This can involve:
- Disconnecting power and refrigerant lines
- Removing the indoor and outdoor units
- Disposing of the system safely and in line with environmental rules
Step 3: Installation of the New System
Next, the new unit is installed. This may involve:
- Mounting the indoor unit(s) and connecting refrigerant piping
- Installing the outdoor unit
- Making any necessary electrical upgrades
- Sealing and testing the system for leaks or faults
- Setting up zoning or remote controls, if applicable
Step 4: Testing and Handover
The technician will test the system to make sure it’s cooling properly, check the airflow and controls, and show you how to use it. They should also explain the warranty and maintenance requirements.
How Long Does It Take?
Most standard installations take one day. More complex setups, like ducted systems or installations in hard-to-access areas, can take two to three days.
FAQs About Replacing a Home Air Conditioner
Still have a few questions before you commit? You’re not alone. Here are some of the most common concerns homeowners have when replacing their air conditioning system.
Do I need to replace the indoor and outdoor units together?
In most cases, yes. Mixing old and new components can cause efficiency problems and may void the warranty. A matched system ensures everything works smoothly.
Can I use my existing ductwork?
If your ducts are in good condition and compatible with the new system, they may be reused. However, older or damaged ducting can reduce performance and may need replacing.
How long will a new air conditioner last?
Most systems last 10 to 15 years with regular maintenance. Choosing a reputable brand and getting professional installation also helps maximise lifespan.
Will a new AC reduce my energy bills?
Yes, especially if your current unit is over 10 years old. Newer systems are much more efficient and often come with energy-saving features that cut running costs.
What kind of maintenance is needed after installation?
Basic tasks include cleaning filters every few months and booking a professional service every 12 to 18 months. Regular maintenance helps your system run efficiently and avoids breakdowns.
Ready to Replace Your AC?
Don’t wait for a complete breakdown or another sky-high power bill. Get expert advice, a transparent quote, and professional installation from licensed technicians who know what works for your home.