Air Conditioners, Dehumidifiers

How To Use A Portable Air Conditioner As A Dehumidifier

portable ac unit lg 2

High humidity can be a big problem when it comes to living comfortably in your home. Living in a hot and humid area can lead to mold and mildew build-up, which can cause some health issues. 

A portable air conditioning unit can help with the heat in your home. But can a portable air conditioner be used as a dehumidifier?

Portable air conditioners do indeed have some capacity to dehumidify the air they suck in. However, they do not work as effectively as a dehumidifier at removing moisture from the air. 

Some portable air conditioning units have a dehumidifier built in them or have a dry or dehumidifier mode. While a portable air conditioner is in its dry way, the fan and the condenser will work together to pull as much moisture from the air as it can.

As you continue to read this article, it will go more in-depth about the process of removing humidity from the air. This article will also compare the effectiveness of both dehumidifiers and portable air conditioners.

Can A Portable Air Conditioner Work As A Dehumidifier?

Portable air conditioners can indeed work as a dehumidifier. However, they will never be as effective at removing moisture from the air as a dehumidifier

This is because portable air conditioners’ primary purpose is to cool the atmosphere of the room they are in. Dehumidifying the air is a side effect of portable air conditioners that cool the air around them. 

The process in which portable air conditioners cool and dehumidify the air happens at the same time. When you turn on your portable air conditioner, it will suck in the warm air in the room where it is placed in. 

Then that warm air will run through the AC unit and eventually reach the condenser coils. These condenser coils have compressed refrigerant running through them at a frigid temperature. 

As the warm air touches the cold coils and the air around them, it will cool down below its dew point. The dew point is the temperature at which air can be saturated with water. 

When air cools past its dew point, the water vapor is condensed to form liquid water. As the water vapor in the air turns into liquid water, it collects into a drip tray. Then the now cooled air is blown out back into the room.

When the water vapor in the warm air is cooled and turns into liquid water, your portable air conditioner will effectively dehumidify the air. 

portable air conditioner 2

How Do Portable Air Conditioners With A Dry Mode Dehumidify The Air?

This process is slightly different if your portable air conditioner has a dry or dehumidifier mode. With the dry setting on, your portable air conditioner makes dehumidification its primary goal instead of cooling down the air it takes in. Your portable AC will do this by slowing down the fan significantly. 

Slowing down the fan allows the air surrounding the compressor and its coils to stay below its dew point longer. 

As this happens, it gives the water vapor in the air more time to condense into liquid water and drip into the drip tray. The dry setting makes your portable air conditioning unit’s dehumidifying ability more effective and efficient. 

With that said, whether your portable air conditioner has a dry mode or not, using a regular dehumidifier is better at removing moisture from the air. 

How Does a Portable Dehumidifier Work?

Portable dehumidifiers work by sucking in warm air from the room. Once the warm air is inside your dehumidifier, it compresses as it moves through compressor coils. 

The air is then cooled down, and the water vapor turns into liquid water. The dehumidifier then collects the liquid water in a water collection tank. This process is similar to a portable air conditioning unit.

The process changes how the air is pushed back out into the room. Here are the steps that are needed to take:

  1. The now cooled air continues through the dehumidifier.
  2. It is warmed back to room temperature by the condenser’s heat.
  3. The now warm, dry air is released back into the room. 

This process has two effects on the humidity level in the room you are using your dehumidifier. First, it dries the air in the room, making it more comfortable and healthy. 

Secondly, as the warm air is recycled back into the room, it allows the existing water vapor in the room’s atmosphere to spread. As the water vapor spreads to the dry air, the humidity level in your room will decrease. 

This process continues as the dehumidifier keeps pulling more and more water vapor from the air.

There are plenty of benefits to wanting to pull moisture from the air. It mainly makes the room more comfortable. However, it will also decrease the likelihood of mold and mildew developing in moist areas in your home. 

Furthermore, dehumidifying the air will also reduce the number of dust mites in your home. Both of these side effects will allow you to live more comfortably and help reduce allergens in the air.

Dehumidifier Vs. Portable AC: Which Is Better For Me?

Both dehumidifiers and portable air conditioning units work to remove moisture from the air. While their process is similar, they work to do it differently. 

If your main goal is to remove water and clean the air, go with a dehumidifier. Dehumidifiers work vastly more effectively at removing moisture from the air than a portable air conditioner. 

Dehumidifiers remove water vapor not only better but more efficiently. As a result, they tend to be much cheaper than portable air conditioners while also using less electricity. 

Your typical dehumidifier will cost roughly $80 to $100 for a reasonably decent one. That said, dehumidifiers will cost you much less to remove the moisture from the air. Add about $5 or so to your monthly electricity bill.

With that said, if you live in a hot and humid area, or cooling down the air is your primary goal, then getting a portable AC unit is the way to go. The reason is that they work to cool the air in their rooms. 

Cooling the air with a portable air conditioning unit will make it more comfortable in 2 different ways. Those ways are:

  • A more controlled atmosphere
  • A slightly less humid one

Both of these will work to make you feel more comfortable while you try to relax.

However, portable air conditioners can be expensive and only work under certain circumstances. Portable air conditioners usually cost $200 to $300+ for a good one. 

With that said, portable air conditioners use a lot more electricity. Running a portable air conditioner will add about $15 to $20 to your monthly electricity bill. 

The main thing you need is an outlet that is near a window. It would help if you had a window because portable air conditioners usually come with vent hoses that cycle the excess uncooled air outside. 

Although you will need a window and an outlet. There are a few different ways to ventilate the extra hot air outside.

Final Thoughts

While portable air conditioning units work to cool the air, they also dehumidify the air slightly as a side effect. Furthermore, portable air conditioners sometimes come with a dry or dehumidify mode, which pulls more moisture out of the air. 

Even though portable air conditioners remove moisture from the air, using a regular dehumidifier will do so more effectively, and more efficiently and will cost you less in the long run.


Hubert Miles | Licensed Home Inspector, CMI, CPI

Hubert Miles is a licensed home inspector (RBI# 2556) with more than two decades of experience in inspection and construction. Since 2008, he has been serving South Carolina through his company, Patriot Home Inspections LLC. As a Certified Master Inspector, Hubert is dedicated to providing his expertise in home inspections, repairs, maintenance, and DIY projects.