how do portable air conditioners work

How Do Portable Air Conditioners Work to Provide Fresh Air?

Ian Mutuli
Updated on
Ian Mutuli

Ian Mutuli

Founder and Managing Editor of Archute. He is also a graduate architect from The University of Nairobi, Kenya.
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Portable air conditioners are convenient cooling devices that come in handy for spot cooling and small spaces. Many people use them in home offices or small disconnected rooms as they are easy to move around, store and install. In addition, most portable AC units are very effective and can be used all year round. But how do portable air conditioners work?

This post will guide you through how portable AC units work in both single and dual hose units. Hopefully, by the end of this complete guide, you will have a clear understanding of how a portable air conditioner works.

What Is a Portable Air Conditioner?

A portable air conditioner also referred to as a stand-up air conditioner, is one of the types of air conditioners that can be carried or moved easily. This device is self-contained, which means it can be placed in any area that is near a window or socket. It comes with wheels that are attached at the bottom, which makes it much easier to move around. Due to its easy movement and placement, it is considered one of the best air conditioners.

Common Portable Air Conditioner Features and Components

In order for portable air conditioning units to work, they should have the following features. However, the features may vary according to the brand.

  • Refrigerant and evaporator coil responsible for cooling the air
  • Compressor for compressing the refrigerant by raising the temperature for the condensation process to take place.
  • A fan to move the air around
  • Condenser coil helps cool down refrigerant

Other features to consider are;

  • Dehumidify or Dry mode to extract moisture from the air without interfering with the temperature of the room.
  • Remote enables you to efficiently operate the AC unit.
  • Auto mode to turn the compressor on and off to ensure the set temperature is maintained.
  • Timer to set a delayed stop or start for the air condition, based on the time of the day.
  • Fan mode to circulate air throughout the room without interfering with the temperature.

With that being said, let's take a look at how a portable air conditioner work to circulate cool air.

How Do Portable Air Conditioners Work?

The main function of a portable air conditioner is to remove heat and transfer the heat outside. These devices work by pulling hot air into the unit, and then the motor cools the air for circulation. It also pulls the excess moisture and warm air and pushes it out of the window through the hose.

Here are the steps as to how most portable air conditioners work;

  1. The fan starts by spinning to draw the hot and humid air from the room to inside the portable AC.
  2. In the AC unit, the hot or warm air is cooled down using the condenser coils to extract moisture from the warm indoor air by condensing the water vapor into the coils.
  3. The hot is then transferred to the refrigerant and the pressure applied to the refrigerant makes it heat up and convert to a high pressure that passes through the AC system.
  4. This collected moisture from the air is then removed by either there the self evaporative system or collected into a pot that will require emptying.

During this cooling process, the refrigerant needs to be compressed using the compressor, and the heat generated from the components needs to be vented out. When the condenser coils become too dirty, the refrigerant may not be able to absorb as much heat as possible.

There are two primary types of portable AC units.

1. Single-Hose Portable AC Unit

Single hose units are the most common ones, and they are cheaper. They come with a single hose that is installed through a window or sometimes through a wall. This one hose is made to serve as an exhaust vent for hot air. It sucks out the hot room air and vents it outside using a single hose.

This portable conditioner unit pulls the air from the room without replacing it. The main problem of this is that the result is the lower pressure in the room, and although you may not feel the low pressure in your eardrums, it will need to be offset somehow. The air from those other rooms is sucked into the room that the air conditioning system. It is vital to limit the access to other hot air, for example, close the door where the unit is operating from.

2. Double-Hose Portable AC Unit

Double hose conditions are more expensive and difficult to install, but they can be able to achieve a higher energy efficiency rating (EER rating). Unlike the single hose conditioners, replace the indoor air with fresh outdoor air. This AC unit works by using;

  • The first hose is used to bring the outside air in.
  • The second hose is used to vent the hot indoor air out.

With these units, you don't experience negative pressure, which means that the air is conditioned better in the room where the unit is. Here are some other benefits of having a portable air conditioner installed;

  • Quicker cooling as the two hoses can help condition the air a bit faster than a single hose unit.
  • Excellent energy efficiency since the unit doesn't need to work against the low pressure, and the EER rating can be more than 10.

These double hose units are not easy to find probably because they are difficult to make. However, with the higher EER rating and eco-friendliness, they are definitely worth every coin.

Using a Portable AC Unit to Cool Hot Air in More Than One Room

A portable AC unit may be able to cool hot air from several rooms, depending on its size. These devices will be able to cool the immediate room, but the cool air won't be able to travel along with the doorways or hallways that are not connected to the space, just like regular window air conditioners.

If you're hoping to cool two rooms that have large openings between them, then the portable unit can work to cool the two areas. However, this cooling of hot air may not be even, and this depends on the size of the unit and the distance between the rooms.

You need to ensure that the two rooms are somehow connected to each other, and the doors are wide open to allow the cold air to flow through them. For two small rooms, you may not need a very large unit. However, it is crucial to understand that there are no cooling devices that can cater to two closed rooms at the same time except for a central air conditioning system, but they are useful when your central air system requires some help.

How Do You Remove Moisture Portable Air Conditioners Collect?

The main difference between how different portable air conditioners work is the way they remove water from the unit. Most of these devices don't require a dehumidification unit as all the portable AC units are dehumidifiers. As the air cools down, they tend to remove moisture from the air.

When it comes to portable ACs, dehumidification is essential because of a number of reasons;

  • The dehumidified air is easier to breathe.
  • The summer air is quite humid, which might cause mildew or mold growth.
  • When the humidity of the air is high, the energy effectiveness of the AC units lowers.

Portable AC units will perform great when it comes to dehumidification as a single is able to remove over 30 pints of water daily. However, this water needs to go somewhere, and there are three main ways as to how the water is disposed of;

1. Self Evaporation

This is considered the best and most convenient method. The moisture is evaporated and flushed out using the hot air exhaust vent.

2. Gravity Drain

Using a gravity drain with an optional built-in pump is also good enough because the collected water is usually pumped out using a drain hose.

3. Bucket

Some options will include a bucket where the water is collected, and you need to empty the bucket manually.

Portable Air Conditioner Requirements

Generally, different models of AC units will have different requirements to help remove hot exhaust air and moisture from a room. Here are some necessary requirements for every portable AC unit;

  • A space next to an opening or window to help connect the exhaust hose.
  • A power outlet of 115 or 120 watts, depending on the unit. However, the portable units which require 14,000 BTUs or more may need their own circuit with a different outlet size.

As you may already know, most air conditioners are designed to use a high amount of energy. So, it is advisable to keep it on a separate circuit, far from other high-energy devices, to avoid overloading one circuit. Always go through the instruction manual to find out if there are some additional requirements of the specific model and brand.

How Do You Properly Maintain a Portable Air Conditioner?

When it comes to portable air conditioner maintenance, several things need to be considered, including;

  1. Clean the exterior of the AC unit using mild dishwashing soap and a lint-free and damp cloth. Remember to unplug the device before you start cleaning to avoid fire hazards and shocks.
  2. Store your portable air conditioning unit in a dry and cool area.
  3. Clean the air filter at least once in two weeks. This is because the dirt and debris collected may clog up the filter for AC units. Use warm water and a dishwashing detergent to wash the filter, rinse it thoroughly, and shake to remove all the excess. Give the filter a few minutes to dry before you take it back to the air conditioner.
  4. Empty the water collection basket or tray weekly, especially if your unit is not self evaporating. This helps to keep the unit clean and prevent mold growth.
  5. To prevent blocked airflow that is caused by trapped hair particles, always wipe the air vent grill.

Tips To Improve The Efficiency Of AC Units

To improve the efficiency of any portable AC unit, here are some tips you should consider.

  • Avoid any sources of humidity by ensuring all the doors and windows are closed whenever the portable AC is on.
  • Place your unit correctly for optimum results. Ideally, this depends on the arena and capacity of the unit.
  • Vent the portable unit correctly to ensure it works properly
  • Clean regularly to keep it free from dust and other particles. You can always use a smart AC controller to determine when it's time to clean the unit.

Pros and Cons of Portable Air Conditioners


  • Easy installation
  • Increased mobility
  • Easy maintenance
  • Great for small spaces
  • Low upfront costs


  • Not energy efficient
  • Noisy

Frequently Asked Questions (FAQs) on Portable Air Conditioners

1. How do you vent a portable air conditioner?

The most common way to vent a portable air conditioner exhaust hose is out a window. Therefore, a window-mounted air conditioner will come with a window kit that fits traditional size windows. Using a sliding glass door or sliding window to vent the exhaust hose is more challenging and complicated than using the window kit. The standard window kits usually are not long enough to extend to fit the entire height of a sliding glass window or sliding glass doors. Exhaust hose lengths vary, and you can always purchase an extension kit for your cooling system.

2. Can you have a portable air conditioner in a room with no windows?

Yes, although a portable is quite similar to a window air conditioner, they can also work in a room where there are no windows. This is because there are other ways for venting the air including through a door, through a wall, or through a ceiling. Also, since the unit is portable, you can always move it around for spot-efficiency cooling.

3. Can a portable AC work without venting?

No. It is impossible for portable air conditioners to work with an air vent. As much as it will normally run when you turn it on, it won't be able to produce cooler air, improve the air quality, or lower the temperature of the room. Portable AC units work by releasing the hot air through the vents.

Ian Mutuli

About the author

Ian Mutuli

Founder and Managing Editor of Archute. He is also a graduate architect from The University of Nairobi, Kenya.