8 ways to run your air conditioner cheaply and efficiently

Stay cool, save cash.

37℃ is the human body’s normal temperature, yet somehow, the task of finding an ideal AC temperature setting to please everybody is virtually impossible. That’s because there’s no objective perfect air conditioner temperature, but rather a whole heap of subjective and highly personal factors that come into play.

Some of the personal factors include how many layers of clothing you’re wearing and the way your body perceives hot and cold sensations (due to body surface area, metabolic rate and body tissue insulation). A 1970s Danish study into office temperatures ultimately concluded that “no office thermal environment ever would satisfy everyone.” 

Environmental factors that have a bearing on the air conditioner temperature include how well your home is insulated, how much direct sunlight hits your house and whether you’re concerned about saving money on energy bills. 

Modern dining room with double height ceilings.
There’s more to running an air conditioner efficiently than setting a temperature and forgetting it. (Photographer: Nat Spadavecchia | Styling: Fiona Gould)

The most energy-efficient air conditioner temperature

Now if you’re trying to work out the most energy-efficient air conditioner temperature setting, that’s a different story. It’s often said that every degree can affect your energy bill by 10%, so if you’re currently setting your air conditioner to 22℃, upping the temperature to 24℃ could save you 20% on cooling your home.

Cameron Evans, industry expert and brand manager for Chromagen says being aware of your home’s thermostat settings could help you save money on power. “In summer, I suggest somewhere around 25 degrees would be the most economical.” 

But there are better ways to save money on your cooling bill than simply setting a temperature on your air conditioner and forgetting about it. Here are eight ways to make your reverse-cycle air conditioner more efficient to run.

1. Take advantage of WiFi connectivity

Even the most affordable reverse cycle air conditioning units come with the ability to connect to WiFi, but do you actually take advantage of this function? By tapping into your air conditioner’s smart capabilities, you can control the unit remotely, tailor the cooling experience to suit your lifestyle and save money at the same time.  

Mitsubishi Electric Australia product expert Atesh Mani says one example where smart controls can save power is overnight. “It can be tempting to leave your AC on all night, but consider whether you can automate your device to switch off after a few hours after you fall asleep. WiFi capabilities will enable you to automate these settings from the convenience of a mobile app.”

If automation isn’t your thing, use the timer function on the air conditioner’s remote to ensure the air comes on just when you need it and turns off exactly when you don’t need it.

Main bedroom
Most reverse-cycle air conditioners can be controlled via WiFi. (Credit: Photography: John Downs | Styling: Kylie Jackes)

2. Clean filters fortnightly

Did you know that you should be cleaning your air conditioner filter once a fortnight? Oops, neither did we. Cleaning the filters will not only help you breathe easier by preventing dust and mould build-up, but will allow the unit to run as efficiently as possible. 

“The dirtier the filter, the harder the air conditioning unit will have to work to maintain the same temperature, meaning higher electricity consumption and more costly energy bills,” says Atesh. It’s also recommended that you replace the air conditioner annually. 

3. Insulation is important

“Proper insulation is the key to reducing your energy bills as it helps to keep your home at a comfortable temperature, meaning that your heater or cooler is only closing the gap,” says Cameron. “Upgrading your ceiling insulation means that you’re reducing heat transfer, and you could end up reducing your bills by up to 45 percent or between $200-$500 for normal households.” reports that the average cost of insulating your home ranges from $1200 to $4000 depending on the size of your home and the type of insulation chosen.

All white coastal apartement with rattan accents
Good insulation will reduce your energy usage. (Credit: Photographer: Mindi Cooke / Styling: Kylie Jackes)

4. Do away with draughts

Even if upgrading your home’s insulation is off the cards, do your best to limit draughts. Some ways to do this include:

  • Buy a door snake to prevent hot air coming in and cool air leaching out (renter friendly)
  • Install rubber weather strips to the bottom of doors 
  • Upgrade window coverings – insulated cellular blinds are a great choice
  • Use gap filler to seal minor gaps in your home
  • Insulate the floor by styling rooms with rugs or carpets

Close the doors to any rooms that aren’t in use to avoid unnecessarily cooling areas of the home.

5. Block out the heat

The glare of the sun can also affect how hot it feels inside your house. Internal blinds and curtains can help to reduce some of this heat, but blocking out the sun before it even gets into your windows (by way of exterior awnings, shade cloths or even a large, shady tree) is even better. 

Keep the blinds drawn during the hottest part of the day (generally around midday) to keep the indoor temperature bearable. 

Coastal home rear exterior painted in Dulux Black and Lexicon Quarter with black and white awnings.
Chic black and white awnings from Bayside Shutters and Blinds protect the upper storey of this coastal home in Avalon from the sun. (Credit: Photographer: Simon Whitbread | Styling: Jamee Deaves)

6. Invest in energy efficiency

Some air conditioners are better at saving power than others. Old central units can chew up plenty of power, while nimble reverse-cycle air conditioners are generally more efficient. When buying a new air conditioner, look at the energy rating of the machine. The more stars, the more savings. 

7. Fan of fans

A simple ceiling fan, or even a pedestal fan, can make your air conditioner cheaper to run. It may sound counter-intuitive, but turning a fan on while your air conditioner is running will circulate the cool air more evenly around a room, meaning you won’t have to set the air conditioner to Arctic to reap the cool benefits.

Contemporary neutral bedroom with ceiling fan and roller blind.
Using a fan at the same time as your air conditioner can help circulate the cool air more efficiently. (Credit: Photographer: Brigid Arnott)

8. Use energy-saving or eco mode

Many reverse cycle air conditioners have an ‘Eco’ button or energy-saving mode. According to Haier, what this button does is reduce the speed at which the compressor runs, meaning the unit consumes less energy.

In some units, eco mode means the unit will cool the room to the set temperature and shut off when that temperature has been reached. The unit will continue to monitor the temperature of the room, and kick into gear again when levels begin to rise. This will keep the room cool but reduce pressure on the machine. Eco mode may also make your unit run more quietly.

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