Can You Use an Air Conditioner as a Dehumidifier?

You may have noticed that your air conditioner seems to do a pretty good job reducing the humidity in your home. So you might be wondering, can you use an air conditioner as a dehumidifier?

The answer is yes. You can use your AC to dehumidify. But there are some things you should know before using your air conditioner for this purpose.

An air conditioner has limitations on how much humidity it can remove from the air. This is where a dehumidifier can come in handy.

To learn if you can use your AC unit to remove humidity or if you need a dehumidifier, continue reading.

a person using the AC’s remote to adjust the temperature

AC Units vs. Dehumidifiers

First of all, it’s important to understand the difference between an air conditioner and a dehumidifier. An air conditioner cools and removes moisture from the air simultaneously. On the other hand, a dehumidifier removes moisture from the air without cooling it.

So, if your only goal is to remove humidity, a dehumidifier will be more effective than an air conditioner.

On the other hand, if you’re trying to cool your home and remove humidity, using an air conditioner is a good option. Just keep in mind that an air conditioner won’t be as effective at removing humidity as a dehumidifier.

How Does an Air Conditioner Work?

how an air conditioner works

Now that you know the difference between an air conditioner and a dehumidifier, let’s look at how air conditioners work.

Air conditioners work by cooling and removing moisture from the air.

  1. The air conditioner pulls air from your home and passes it over a cooling coil.
  2. This cools the air, and moisture condenses onto coils. Cool air doesn’t hold as much moisture as warm air.
  3. The water droplets then drip into a condensate pan out out of a drain tube.
  4. The cold air is then blown into your house.

How Does a Dehumidifier Work?

diagram showing how a dehumidifier works

A refrigerant-based dehumidifier works by removing moisture from the air.

  1. Like an AC, it pulls air from your home and passes it over a cooling coil.
  2. However, rather than blowing air back into your home, the air is filtered through a dehumidifying filter and passed over a heating coil.
  3. This removes excess moisture from the air and releases dry air back into your home.

Info: The less common desiccant dehumidifier uses a different technology that absorbs moisture.

Can You Use an Air Conditioner as a Dehumidifier?

a person using the remote to turn on the AC

AC units and dehumidifiers use the same methods to remove humidity from your home. But can you use an AC unit as a dehumidifier?

The answer is yes, but there are some things you should know before using your air conditioner for this purpose.

Air conditioners have limitations on how much humidity they can remove from the air. Their primary function is to cool your home, and they will only condition the air until its temperature reaches the setpoint on your thermostat. 

So, if your climate is very humid, your AC unit might cool your home down to your desired temperature but leave excess humidity in the air. Remember, dehumidification with AC units is just a byproduct of decreasing the air’s temperature. 

Using your air conditioner as a dehumidifier will cause your energy bills to increase. This is because air conditioners use more energy than dehumidifiers.

If your goal is to remove as much humidity as possible, a dehumidifier is the better option. It will be more effective than an air conditioner and will save you money.

Can You Use an AC Unit and Dehumidifier at the Same Time?

Yes! You can use a dehumidifier and an air conditioner at the same time. As we discussed, air conditioners are great at decreasing the humidity of the air. But, they can only remove so much.

If there is too much moisture in the air, your home might still be humid even with the AC running.

So, if you live in an extremely humid and hot climate, you may have to use both. In fact, many HVAC professionals recommend it for optimal home comfort. That is why many homes in the Southeast U.S. have whole-house dehumidifiers.

FAQs

Here are some common questions we get about dehumidifiers and AC.

How do I know if my humidity is too high?

Most thermostats monitor relative humidity (RH) along with the temperature. If your thermostat does not measure humidity, you can use a hygrometer

What humidity level should I keep in my home?

Comfortable humidity is around 30-60% RH. Above 60%, your home will feel damp and sticky, and you may have condensation on your windows. Below 30%, you start to feel dry and itchy.

Improper humidity levels can cause sinus irritation, allergies, itchy eyes, chapped lips, dry skin, and a host of other problems. It can even negatively impact your sleep. Thankfully, you can easily balance the humidity in your bedroom with a portable dehumidifier.

If it is cold outside and humid, can I use my AC to dehumidify my home?

Yes, you can. But I wouldn’t recommend it. Since it is cold outdoors, you will likely need to run your furnace too, and running heating systems simultaneously as AC is not at all energy-efficient (or logical). In these rare cases of cold weather and high humidity, use a dehumidifier (and not your AC unit).

Run Your AC or Dehumidifier Wrap Up

Your air conditioner dehumidifiers your home– it is a byproduct of cooling it as cool air can’t hold as much humidity as warm air. In many cases, running an air conditioner is good enough to lower the humidity in your home. But if your climate is extremely humid, you may need to use a dehumidifier to help keep up.

About The Author

Jonathon is a mechanical engineer with over ten years of experience in the HVAC industry. He has hands-on experience with all types of HVAC systems.

Leave a Comment