How Long Should An Air Conditioner Run To Cool A House?

Advice and News •

How Long Should An Air Conditioner Run To Cool A House?

air conditioner running constantly

On blistering hot summer days, it’s tempting to leave your air conditioner running constantly. But did you know leaving your air con on all day can wear out your AC faster and cause your electricity bills to skyrocket? In this article, we tackle some of the myths about leaving your air con all day.

Is It Safe To Leave Air Conditioner On All Day?

While it may technically be safe to leave your air-con all day, it’s not usually the smartest decision. Why? Because it wastes electricity, makes your energy costs soar, and speeds up the demise of your air conditioning unit.

Here are some reasons why running your air conditioner 24/7 might be doing more harm than good:

Your Air Conditioner Isn’t The Right Size For the Room

It’s simple: Running your air con all day means higher electricity bills due to less efficient power. This usually happens if your air conditioner is too big or too small for your living space.

You’ll know the air con isn’t the right size if your air con has trouble consistently meeting the temperature you set in a timely manner, so you’ll be forced to run it for longer. An oversized unit will tend to cycle on and off (short-cycling), while an undersized unit will struggle to be powerful enough to cool your home. In both cases, your air con will wear itself out faster.

If your home needs a new air conditioner, make sure your air conditioner installer calculates precisely how much cooling capacity is needed for your home. This should take into consideration your home’s layout, insulation and the number of heat-generating appliances.

Your Air Conditioner Isn’t Placed In The Correct Position

Did you know the location of your air conditioner has a huge impact on its energy efficiency? While it may seem convenient to place a bulky air conditioner in an unused corner of your home, this ultimately means your air con will need to work harder to cool your entire house.

If you install your air conditioner outside your home, make sure to clear away any shrubbery that might block air flow first. Your outdoor air conditioning unit will need this extra space to properly cycle air through your home.

You Don’t Run Your Air Conditioner Often Enough

While it’s not a good idea to have an air conditioner running constantly, it’s also best to avoid letting it sit unused for long stretches of time. Leaving your air con idle gives mould a chance to grow inside. Make sure to run your air con for a few minutes every day in summer.

Your Thermostat Is Set Incorrectly

Turning your air con to a lower temperature will not actually cool your room faster. Instead, try to reduce the thermostat’s temperature gradually to avoid putting too much stress on your air con.

You’re Not Making Use of Ceiling Fans

A ceiling fan can greatly enhance your air conditioner’s reach by circulating more air around your home. In comparison to solely relying on your air con, using fans will also save you money.

How Long Should Air Conditioner Run To Cool A House?

Assuming your air conditioner is the correct size for your home, your air conditioner should cool your home in a 15-20 minute cycle. If it’s a particularly hot or humid day, it will likely need to run longer to reach your desired temperature.

If your air con runs for 20 minutes without impacting your home’s temperature, your air conditioner may be too small for your space. In this case, you’ll need to upgrade your air con’s size.

An air conditioner that is too big for your space will short cycle and cool your home too quickly, in roughly 10 minutes or less. While theoretically reaching a cool temperature faster sounds like a benefit, this short cycling means your air con won’t effectively decrease humidity in the air, leaving you feeling hot and sticky. Even worse, your air conditioner will become overworked and need more repairs.

A Quick Checklist: Factors That Impact How Long Your Air Conditioner Runs

  • The temperature outside – The hotter it is, the longer your air conditioner will need to run to reach your desired temperature.
  • Your thermostat’s setting – The lower you set your thermostat in summer, the longer your air conditioner will have to run to reach it.
  • Your air conditioner’s size
  • The state of your air conditioner – When you take good care of your AC, it will continue operating efficiently – it’ll even have a longer lifespan. A neglected air conditioner does the opposite. It won’t cool your home and need to run longer to reach your desired temperature.
  • The size of your home – A larger home will take a little longer to cool, especially if the air conditioner unit is on the small size.
  • Your home’s insulation – A lack of quality insulation means much of your cool air is actually leaking outside. Ultimately, this means it’ll take much longer to cool your home, and your air conditioner will need to run longer to compensate for the loss.

How To Keep Your Home Comfortable With An AC

So what’s an easy solution to keep your electricity bills low, yet keep your home cool and comfortable? To reduce the runtime for your air con, try strategically cooling only the rooms you’re currently using by closing doors. Adjusting your thermostat even just a couple of degrees to a warmer temperature will also help your air con reach the set temperature on time and save you money on electricity costs.

Need help figuring out why your air con takes so long to cool your home? We’re here to help. Get in touch with H&H Air Conditioning on (07) 3276 1800 (Brisbane) or (07) 5477 1777 (Sunshine Coast).