What is the best temperature for AC?

It happens every year. Outdoor temperatures start heating up, you turn on your central air conditioning, and now it’s decision time: What temperature should I set my air conditioner in summer? According to the Department of Energy1, 78° Fahrenheit is the sweet spot for air conditioners to balance energy savings and comfort when people are at home and need cooling. But in reality, this is a question that doesn’t have a “one size fits all” answer.

Determining the right answer for you will require some experimentation with different settings. It will also require determining whether you are more interested in achieving lower electricity bills, higher comfort levels or a balance of both. Other factors that can affect the best temperature for AC in your home include the number of people, amount of physical activity, and exterior factors like humidity, amount of direct sunlight, number of windows, and more. Ultimately, the best AC setting for your home is the one that makes you and your family comfortable with utility costs you can afford.

What Temperature Should I Set My Air Conditioner in Summer?

When the heat and humidity have you working up a sweat, the temptation is to crank up the AC and enjoy that nice, cool, dry air. Then you get your utility bill and it hits you... there’s a price to pay for all of that extra comfort. You want to save money, so you set your thermostat several degrees higher and the cycle starts all over again. If this sounds all too familiar, there are some ways to find that comfortable balance between comfort and savings.

Start by setting your thermostat higher than normal when you are away, and at 78 degrees when you are home. That is the Department of Energy’s recommended setting when you need cooling, but want to save energy. If you find that your home is too hot for comfort, try reducing the temperature setting by a degree or two to see if you feel cooler. Continue to reduce your temperature setting by one or two degrees until everybody is consistently comfortable. As you experiment with finding the setting that works for you, consider using some of the energy-saving and comfort-enhancing tips that follow.

Set the Thermostat at a Higher Temperature When Your Gone

One simple way to decrease energy costs is having a higher temperature setting on the thermostat when nobody is home. While you might be tempted to simply turn the AC off, it’s actually better to adjust the temperature several degrees higher, by about 7-10 degrees. By installing a programmable thermostat and making this simple adjustment you can potentially save as much as 10% on your energy bill.1 Completely shutting down the system might actually cost you money due to the extra energy it takes to cool your home back down to your comfort zone.

Another habit to avoid when looking for the best temperature for AC settings is setting the thermostat on a colder setting to cool the home down more quickly after you’ve been away. Your air conditioner will not cool any faster – it will cool at the same rate, but will run longer until it reaches the lower temperature. In the long run, that extra cooling can actually result in an unnecessary expense. If you don’t already have one, a better solution is to use a programmable thermostat or even a smart thermostat. These thermostats can be set to automatically raise the temperature when you are away and re-set the system for a more comfortable temperature by the time you return. With a smart thermostat, you can adjust the settings wherever you are, using a connected device like a smart phone or tablet.

Turn on the Ceiling Fan (And Other Natural Solutions to Cool the Home)

Some simple tricks for potentially saving money might be right there in front of you. If you have ceiling fans installed in your home, use them! Increasing airflow in a warm room won’t reduce the temperature, but it will help to make it feel cooler and more comfortable. And, running a small fan takes less energy than running the air conditioner. If you don’t have ceiling fans, a standalone fan can have the same effect. Available in a variety of sizes and styles, from a small desktop fan to a larger box fan that sits on the floor or even a narrow-profile tower fan, you can find one that fits your budget and can be moved from room to room as needed.

Additional comfort-enhancing (and money saving) suggestions include:

• Closing window coverings during the day to reduce heat from sunlight.
• Turn off your AC and open windows at night to naturally cool your home. Shut the windows during the day to seal in the cooler air.
• Add weather stripping to window and door openings to better seal in comfort and seal out heat.
• Avoid using heat-generating appliances such as an oven, your clothes dryer, hair dryers, etc., especially during the day.

Perform Regular Maintenance on Your Air Conditioner

Even ENERGY STAR® certified air conditioners need some regular TLC to deliver their expected efficiency ratings. Because much like your car, your central air conditioner operates more efficiently with routine maintenance and system check-ups. For example, a dirty, clogged air filter can restrict air circulation, potentially causing loss of comfort and reduced energy efficiency, while also putting a strain on the system’s fans and motors. As a part of standard AC Maintenance, most homeowners can handle checking, cleaning or replacing the air filter. However, experienced HVAC professionals have the training and the equipment to dig deeper. They can assess system performance, clean and adjust internal components and take care of any minor issues before they become big problems. A professional air conditioner tune-up can help maintain the efficiency of your system with services like:

• Cleaning the outdoor coil: A dirty outdoor coil affects system performance by restricting airflow and heat transfer needed for proper cooling operation.
• Cleaning the evaporator coil: A dirty evaporator coil affects system performance by restricting airflow and heat transfer needed for proper cooling operation, and can affect indoor air quality with build-up of mold and bacteria.
• Checking refrigerant levels: Low refrigerant levels can reduce cooling capability, causing the system to run longer and use more energy trying to maintain comfort.
• Cleaning and adjusting blower components: Your indoor blower circulates indoor air through the system and returns cool air back to your home. A poorly functioning blower can affect both comfort and energy costs.
• Installing a smart thermostat: As mentioned previously, installing a smart thermostat can help you more effectively manage your temperature settings. Consider having your dealer install one during one of their regular scheduled tune-up visits.

What is the Best AC Temperature for Sleeping?

Although 78⁰ F is a good temperature for energy savings and comfort when you are home and awake, it is not ideal for slumber. In fact, bedroom temperatures that are too hot or too cold can result in a restless night. A general recommendation is that the optimal temperature for sleeping is between 60⁰ and 67⁰ F, regardless of the season outside.3

• To help ensure a better night’s rest, consider re-setting your thermostat before you go to bed, leaving enough time for the temperature in your bedroom to adjust.
• If you have a programmable thermostat, you may want to schedule it to automatically reduce the temperature during the times you are normally asleep.
• If it works for you and your climate, try opening a few windows. This method will depend upon having milder, cooler outdoor temperatures, and offers a more energy-efficient, but less precise, option for achieving the targeted 60⁰ - 67⁰ F. Be sure to close the windows in the morning to seal in the cooler air.

The above recommendations are for a typical adult. Keep in mind that infants and small children should be in rooms with a slightly higher temperature to ensure better, more restful sleep.

1See Department of Energy's Spring & Summer Energy Saving Tips

2See Department of Energy's Energy Saver 101 infographic.

3See the Cleveland Clinic's information on ideal sleeping temperatures.

Air conditioners are an escape from the blistering heat outdoors. You turn your air conditioner on every day, especially when temperatures begin to heat up. You have a decision to make each time you use your aircon, and that is to figure out the temperature to set the appliance. What is the ideal temperature setting for air conditioning during summer, winter, or when the weather is quite pleasant? This question is what this blog aims to answer, so keep reading.

The Difference in Degree Settings for Comfort

Energy agencies in many parts of the globe agree that 25-26 degrees Celsius (78F) offers the sweet spot. This temperature range balances comfort and energy savings for homeowners as it satisfies their cooling needs without costing too much. In reality, however, it is not a one size fits all situation.

Figuring out the answer to the question often requires experimentation. You will also have to choose between having lower electricity bills and a more comfortable space at home. Or are you more interested in enjoying a balance of both?

You also have to know that certain factors affect the temperature in your home, such as the number of residents, your physical activity, humidity, number of windows, and the direct sunlight the house receives. Ultimately, the best temperature setting for air conditioning is the one that keeps you and your family happy and comfortable. At the same time, you have utility costs that you can pay for without any problems.

One thing that you need to remember is that air conditioners work harder for you to feel comfortable at home. Their job is to offset extreme temperatures, whether you live in a warmer or cooler climate. Efficiency is essential, but you should not fail to recognise everyone’s comfort levels.

Cooler Climates vs Warmer Climates of Australia

In Australia, the most efficient aircon temperature generally depends on the climate and season. Summers differ vastly based on your location, whether you’re in the southern regions where summertime is often cooler than other places, or you’re located at the tip of the country where summers are unbearably hot. However, no matter how diverse climates can be, many Australians prefer an air conditioner setting of 22 degrees in the summer months and 19 degrees in winter. 

For example, in southwest Western Australia, where there’s a Mediterranean climate, you can benefit from 23-24 degrees in an air conditioning setting in the summer. In the winter, 18 degrees is the most commonly used temperature setting. Let’s compare these settings to Tasmania, where there is a mild temperate climate. In the summer, the recommended aircon temperature is only two degrees. Air conditioners often work from 21 to 22 degrees in the winter.

Meanwhile, in the Australian Capital Territory, where the population enjoy an oceanic climate, the best temperature in the summer is between 26 to 27 degrees. The ideal temperature is around 19 to 20 degrees during the winter months.

Even with the temperature range given above, it is still necessary to adjust the settings. Each person and household can have varying levels of comfort. There may also be a cold snap during summertime, so homeowners may have to adjust their summer settings to fit colder conditions. Temperatures can increase significantly, which means that settings should adopt warmer summer months.

Once again, the temperatures differ greatly depending on your preferences. However, it makes sense to consider the outdoor temperature when setting your aircon. For example, if it is 24C outside at night, it’s not recommended that you set your AC to 25C. Why not just open your windows. When humidity is high, you will sleep soundly if you set your aircon about 1-2 degrees cooler than outdoors.

Take note of humidity in your area. High humidity can turn hot days into a more significant challenge. Your sweat glands do not normally work because of the moisture in the air. Sweat dissipates quickly when the air is dry, keeping you more comfortable. When humidity rises, however, the water vapour in the air increases, making it difficult for sweat to evaporate.

Fortunately, air conditioners are great for reducing humidity. They work even more efficiently when your home is properly sealed.

Temperature Settings and Energy Costs

According to the Department of Energy, cranking up the aircon one degree at a time immediately increases energy costs by 10%. Imagine using the aircon set at 25C for 15 hours a day or more. You will surely see a drastic change in your bills. For this reason, many homeowners are seeing the benefit of setting the thermostat to 24-26C during summer and 18-20C in the winter.

It’s difficult to know how much your aircon contributes to your total energy costs. But here’s something easy to remember. The harder the aircon works, the more energy it requires. This immediately results in higher electric bills. Other factors affect the cost, including the cooling capacity of your aircon.

For example, setting a 2.5kW AC to 21 degrees could cost you around $0.16 per hour. Setting it to 22C will give you an hourly rate of $0.14, while 25C may cost about $0.11. A 3.5kW system, on the other hand, costs $0.26 per hour on 21C. If set to 25C, hourly costs maybe around $0.18.

Of course, the mentioned rates above are merely an example. You have to consider the sealing and insulation of your home and the type of aircon you are using. Make sure you have one that’s rated energy efficient to help you save money. It would help if you also thought about switching to alternatives to aircon, such as ceiling fans.

Does Running Ceiling Fans at the Same Time Help?

Ceiling fans surely help in keeping cool air in your room. They can work with your aircon so the equipment can assist in distributing air throughout the house, meaning there will not be warm spots anywhere. Turn on the ceiling fans whilst your aircon is running in summer mode. The fan will keep cool air down while keeping warm air away from you.

If you are worried about your bills, replace your AC with ceiling fans at night – even on hot days. Open the windows and let the cool breeze in to save more money.

Remember, though, that ceiling fans will not change the temperature of the room. However, they do help in making the space feel more relaxed and more comfortable. With your ceiling fan and aircon working simultaneously, you can use a higher temperature setting without using more energy.

Are There Any Differences in Ducted vs Split Settings?

Many experts and homeowners agree that a reverse cycle ducted system is the best choice in keeping cool and hot air in the house when needed. That’s why it is a good idea to invest in the said system to ensure heat is never trapped inside again. The flexibility of a ducted system is noticeable, especially if you have been using a cheaper aircon for several years. Ducted systems work to cool your house during summertime and keep it warm in winter. They reverse the refrigeration cycle when necessary to provide the most optimal setting and reach the ultimate comfort level for you.

However, if you are not too keen on the cost of ducted systems, there is a more affordable option: split air conditioning. This type of AC offers zone-smart air conditioning, which allows you to cool one room at a time. If you have a smaller house or a few rooms, split ACs may be better. However, the zonal effect can also be achieved with a ducted aircon. So, if you’re merely going for this particular benefit, it may be wiser to pick a ducted system, especially if you have more than one room to cool.

The easiest way to ensure you get the most out of your aircon is to install a temperature sensor. It’s useful for a ducted system as it works to measure the temperature inside the house, sending the data to your thermostat. As a result, your thermostat will adjust the temperature accordingly.

Whether you choose a ducted or split air conditioning system, you should always hire a licenced person to install the equipment for you. It is worth the additional cost. Installing on your own can cost you the manufacturer’s warranty, which is often void if a non-licensed person does the installation. Make sure that the system is carefully and routinely serviced, as well.

Contact ACSIS to get affordable and professional air conditioner services in Perth.