Cutting your aircon running costs in WA without buying a new system

Running costs are the part of owning an air conditioner that keeps adding up long after the installation invoice is paid, and there’s a fair bit you can do to bring that down without spending a cent on a new system.

Start with how you’re using it, not the unit itself

The single biggest lever most households haven’t pulled is the thermostat setting itself. Every extra degree of cooling makes the compressor work harder and run longer to get there, so nudging the setting up slightly, particularly overnight when a very cold room isn’t necessary for comfort, reduces how hard the system has to work without making the home uncomfortable. A steady, moderate setting through the hottest part of the day also tends to cost less than switching the unit fully off and then blasting it back on to fight a hot room from scratch.

Keep the system itself efficient

A dirty filter is one of the most common, and most overlooked, reasons a system costs more to run than it should. A blocked filter restricts airflow, which forces the compressor to work harder for the same result. Cleaning or replacing filters every few months during heavy use, on top of an annual professional service, is one of the simplest, lowest-cost habits that keeps running costs in check. Our energy efficient and green systems hub lists Perth specialists if you want a proper efficiency check on an existing system.

Simple habits that add up

A few changes around the home make a real difference without touching the system itself:

• Close curtains or blinds on windows that catch direct afternoon sun, since blocking heat before it enters the room means the system has less work to do.
• Use ceiling fans alongside the aircon rather than instead of it, since moving air can let you run the thermostat a degree or two higher while feeling just as comfortable.
• Seal obvious gaps around doors and windows if a room struggles to hold its temperature, since conditioned air leaking out means the system runs longer to compensate.
• Only condition rooms in use, closing vents or doors to unused rooms if your system allows it, rather than cooling the whole home for one occupied room.

When it’s worth a professional check rather than a new system

If running costs feel higher than they should be even after the basics are covered, it’s worth getting a technician to check refrigerant levels and overall system health before assuming a full replacement is necessary. A system running low on refrigerant, or with a coil that needs cleaning, can cost noticeably more to run for the same cooling result, and that’s often a service job rather than a reason to buy new.

Change	Cost	Typical impact
Adjusting thermostat setting	Free	Meaningful reduction in running time
Cleaning filters regularly	Free to low cost	Keeps airflow efficient, avoids overworking the compressor
Ceiling fans alongside aircon	Low cost if already installed	Lets you run a slightly higher, still comfortable setting
Sealing gaps around doors/windows	Low cost	Reduces conditioned air loss
Professional refrigerant check	Cost of a service call	Identifies inefficiency a filter clean won’t fix

Bill assistance is worth a quick check

If running costs are a genuine strain rather than just an annoyance, it’s worth a direct conversation with your energy retailer or WA’s Department of Communities about available concessions or hardship support. Eligibility criteria shift and aren’t always intuitive, so a quick call to confirm is a better approach than assuming you don’t qualify. If you or someone in your household is a senior or pensioner, our guide on air conditioning support for seniors and pensioners in WA covers concession schemes in more detail.

Comparing running cost against the price of a new system

It’s worth being realistic about how much a habit change can achieve. If a system is genuinely old, undersized for the space, or has an inefficient compressor by today’s standards, no amount of thermostat discipline or filter cleaning will bring the running cost down to what a newer, better-matched system would achieve. Habits and maintenance close the gap on an otherwise sound system; they don’t fix one that was the wrong size or a poor match for the space from the start.

A realistic order to try things in

Start with the free changes: thermostat setting, closing curtains against direct sun, and checking the filter. Move on to the low-cost habits, ceiling fan use and sealing obvious gaps, if the free changes aren’t enough on their own. Only after that is it worth paying for a professional refrigerant or efficiency check, and only after all of that would it make sense to seriously consider whether the system itself, rather than how it’s used, is the actual problem.

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