How To Set Mini Split Temperature

You’ve installed your mini-split air conditioner, and what a marvel it is! Now, you need to set the temperature for round-the-clock comfort.

What’s the best temperature for the summer? What about the winter when you’re using the mini-split as a heat pump? Above all, where should you install the thermostat if you’re using a wall thermostat? We answer these and several other questions related to mini-split temperature settings below.

Why Set it to s Specific Temperature?

Perhaps we should begin by discussing why you should set the thermostat to a specific temperature. Why not any temperature? There are four reasons;

Ultimate comfort

The main reason you’re buying the air conditioner in the first place is to improve comfort levels in the home. You can only achieve the desired comfort within a specific temperature range. Beyond the comfort range, the room becomes either too hot or too cold.

It’s good for your health

According to the World Health Organization (WHO), humans are most comfortable between 64˚F and 75˚F. However, if someone in the house has a chronic condition, they need temperatures between 68˚F and 75˚F. You’re exposed to various health issues outside this range, including heat exhaustion (extreme heat) or allergic reactions (in extreme cold).

Good for energy savings

Heating and cooling account for more than half of energy use in the home yearly. It’s incredible when you consider that we only need heating and cooling for a combined six or so months per year. Keeping your thermostat settings within a suitable range can lower the eventual power bill.

It’s good for your HVAC system

The mini-split air conditioner is at optimal health when running at optimal speed. If you set it too low, the cooling cycles maybe longer, which can accelerate wear and tear. If it’s too high, it puts extra strain on the AC, leading to faster wear and tear. Faster wear and team means more (and costlier) repairs and shorter appliance life.

Factors Affecting Thermostat Settings

As you may have noticed, we gave a temperature “range” rather than a fixed thermostat setting. The reason is that different people are best different temperatures depending on various factors as follows;

Time of the year

The first and most important consideration is the season of the year. When it’s sweltering hot inside the house during the summer, you need to keep the thermostat low to mitigate the dangers of overheating. However, when the cold season sets in around December (or November for some places), you’re required to raise the thermostat slightly to draw more heat into the house.

Time of day

The time of day is just as important. The home is typically coldest in the early morning and hottest in the later afternoon. As such, you may want to keep morning temperature settings slightly higher and the afternoon temperature settings a tad lower irrespective of the time of the year. However, you’re allowed to keep the thermostat lower when you go to sleep to save on power.

Which part of the house?

 Different areas of the house may also require different thermostat settings for ultimate comfort. For instance, rooms directly exposed to sunlight are typically warmer, thus allowing you to keep the thermostat lower in winter and higher in summer. Rooms on upper floors also tend to be warmer because warm air rises. Meanwhile, basements are typically colder than the rest of the home.

Humidity levels

Although it escapes most peoples’ minds, humidity levels also determine the ideal thermostat setting. If you live in a humid area, you may need to keep the mini-split running longer to remove the excess moisture.

Personal preferences

Finally, everyone has a different preference. Some people prefer slightly warmer environments, while others feel more comfortable in slightly colder places. You can also adjust your thermostat settings to reflect these preferences.

What is the Best AC Temperature for the Summer?

As we’ve mentioned, summers are scorching hot, meaning that you need to keep the thermostat set lower than outside temperatures. Summers are also typically more humid than the colder seasons. Consider the following thermostat settings;

When you’re home

The best AC thermostat setting when you’re home in the summer is 78˚F. It’s a great setting for optimal comfort while also guaranteeing energy savings.

However, keep in mind that 78˚F is slightly higher than most people’s preferences. The majority of people keep their air conditioners around 72˚F, with a few even going below 70˚F.

So if you want to save energy while remaining cool enough, 78˚F or thereabouts would be an excellent choice. You can begin at 70˚F and adjust it slowly after, say, every 10 minutes until you get to 78˚F.

When you’re away

 The air conditioner won’t be heating anyone when you’re away. This allows you to raise the setting even higher. According to the Energy Department, you should set it between 85˚F and 90˚F until you return home.

However, turning it off wouldn’t be a good idea. For one, it puts extra strain on the central air conditioner. The added strain can shorten the life of the central AC. Additionally, the overly hot conditions in the home can worsen humidity issues in the house, which isn’t ideal for your books, furniture, and wall paint and wallpaper.

What’s the Best Temperature for Winter?

Winter, being extremely cold, requires that you raise the heat pump setting (compared to outdoor temperatures). At the same time, you must select a setting that allows you to save energy. We recommend the following thermostat settings;

When you’re at home

The Department of Energy recommends keeping the thermostat at 18˚C, which is equivalent to 64.4˚F. You may be tempted to lower it even further, perhaps to save on energy. However, don’t forget the overly low temperatures cause all kinds of respiratory issues.

Since 64.4˚F is also a little too cold for most people, you can begin at a slightly higher setting, say 70˚F, and gradually adjust until you reach the optimal setting. You may also want a slightly higher setting, say 67˚F, on freezing-cold days.

When you’re away

Just as in the case of heating, you can lower the thermostat slightly when you’re not home to save on energy as the AC won’t be serving anyone. According to the Department of Energy, any setting below 60˚F would be fine. However, you can set it as low as 55˚F without adverse consequences.

Again, don’t shut off the heat pump completely. Doing so puts the central furnace under massive strain. Furthermore, it may result in overly dry conditions that may cause your furniture to warp and house plants to wither.  

Additional Tips

We must mention two things. First, where do you change the settings? Although nearly all air conditioners have onboard controls from where you can change the thermostat settings, some arrive with wall thermostats only.

Also, more modern air conditioners allow you to make the changes on a smartphone application or via intelligent voice systems such as Amazon Alexa and Google Assistant.

Secondly, whichever the season, you can (and should) always take extra steps to improve indoor comfort while minimizing energy usage.

For instance, closing the blinds to keep out the sunlight during the day and opening the windows at night can allow you to raise thermostat settings in the summer. At the same time, setting the fans to rotate clockwise can lower energy usage in winter.