Is It Safe to Leave Air Conditioner on All Day? | How Long Should AC Run

If you live in an oceanic or tropical climate, you know how hot and humid the summers can get. And, being uncomfortable in your own home is something that no one wants.

As a homeowner, I know just how tempting it can be to want to keep the AC running around the clock. But is it safe to leave air conditioner on all day and night? Let us dive right in to find this out.

Is it Safe to Leave Air Conditioner On All Day

The answer is “yes.” Letting your air conditioner run all day will not cause any harm to you or your family. There is no standard amount of air conditioning beyond which it becomes dangerous or harmful.

Should You Leave Your Air Conditioner On All Day?

While it is generally safe to leave your AC running throughout the day, doing so may not be safe for your bank account. You might consider getting an energy-efficient air conditioner for that matter. 

We all love that easy-breezy sensation that engulfs us when we retreat into the cool confines of our air-conditioned homes. But, can we keep our homes this cool all day and save money on the energy bills simultaneously? Tough job! 

Then again, turning off the AC can cause the indoor humidity levels to soar. And with that comes the danger of increased mold and bug infestation.

If it is not a good idea to turn off the AC or leave it on all day, what is the way forward then?

At this point, it may seem like there is no direct answer to this question. But let us find it by first looking at the reasons for and against running your air-conditioning throughout.

Why it is Inappropriate to Keep the AC Running 24/7

Much as you would want to leave the AC on all day to beat the humidity and keep your house comfortable, there are some strong reasons against it.

1. Higher electricity bills

Your air conditioning equipment is a sophisticated system that works hard to keep your indoor temperatures at comfortable levels. To keep up this work, they require a lot of electricity.

Unless you are using a type of solar-powered conditioning unit, high electricity consumption could cause your energy bills to skyrocket.

The problem is, standard AC systems do not always have the solar option. 

2. Energy wastage

Whenever you run the AC continuously, a significant amount of the energy powering the system goes to waste.

Air conditioners only need to run for a certain amount of time to get the room to the desired temperature. After that, it can cycle off to save energy.

Keeping it running after reaching the desired room temperature means that the extra energy is wasted.

3. Too much strain on the AC

Like any system, the air conditioning unit needs time to rest. Running it nonstop puts too much strain on it. This kind of strain could lead to premature system shutdown.

Even if the AC unit does not completely shut down, it will likely break down sooner than it should due to overworking.

Eventually, the stress will take its toll, and the unit might not last as long as the manufacturer intended.

How does this affect you? Think about the trouble of having to replace the whole thing altogether sooner than you had budgeted for. 

4. Impact on the environment

There is increasing awareness of how our activities impact flora and fauna around us. With this in mind, you may want to know that your AC usage can be a significant contributor to global warming. 

Heating, ventilation, and air conditioning (HVAC) units increase greenhouse gas emissions through increased energy usage. The more you leave them running, the more carbon footprint they contribute to the environment.

These systems also leak organic compounds called hydrofluorocarbons (HFCs) into the air. HFCs are some of the most potent ozone-depleting compounds that lead to global warming.

On the flipside…

You also do not want to leave your home without air conditioning for long because this could cause indoor humidity to go through the room.

As we have mentioned, high humidity could be synonymous with increased mold and bugs problem.

Fighting molds and bugs can present you with additional costs you don’t want – not to mention the health effects they might have on your family.

You see, the air conditioner does more than just cool the air inside your home. These cooling units also help filter the indoor air, removing potentially disease-causing dust mites and mold spores from the air.

ACs also help to dehumidify your home. So when you turn it off and let it stay that way for a while, it will not be long before the humidity hits the roof.

Condensation will ensue, promoting mold growth and bug infestation.  For that reason, you might want to get a dehumidifier to help with humidity control.

One workaround to this problem is to turn up the thermostat instead of switching off the AC when you are away. This will save you money and keep your home from the intruders we have mentioned above.

How Does Turning Up the Thermostat Save You Money?

Suppose you increase the indoor temperatures by one or two thermal units; you decrease the gap between the indoor and outdoor temperatures.

There will be less work on your AC, and it will be happy to reward you with reduced energy expenditure.

You may not realize it, but increasing your home’s indoor temperature by one degree can mean 5-percent less work on your air conditioner.

Less work means less power consumption, which translates to increased savings on the energy bill.

Can You Remember to Turn Up the Thermostat Whenever You are Leaving for Work?

You do not have to commit to raising the thermostat each time you leave the house. An easier and more reliable alternative is to invest in a programmable thermostat.

Amazon has tons of these to suit every budget and air conditioning preference. So you can choose what works best for you.

Once you have chosen the preferred setting, the programmable thermostat will automatically change the temperature for you.

So then, instead of worrying about switching off your AC and back on now and then, use your programmable thermostat to create a schedule instead.

Then, let the device increase the temperature when you are not around to allow the system to be off more often. This should be the most efficient way to use your air conditioner. 

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Melanie Mavery is an aspiring HVAC technician who is fascinated by the trends and opportunities in the HVAC industry. She spends most of her day writing content on home improvement topics and outreaching to prospects.  She's always looking for ways to support HVACs!