How Does A Portable Air Conditioner Works? (With FAQ!)

There are a lot of questions revolving around portable air conditioners that are left answered. Many are confused about how does the AC work; it is efficient in cooling, and what is the best option available. In this post, we will address it all for you to understand how portable air conditioners work. We will also touch on the pros and cons of owning one, so you can make a sensible choice about whether to purchase one. Read on.


How Do Portable Air Conditioners Work?

Powered by refrigerant technology, Portable air conditioners work by pulling hot air into the unit, cooling it internally, and releasing cool air into the room. Heat and excess moisture are expelled outside via a hose, away from the room. Unlike a central air system, ductless AC, or window AC with two separate unit systems, portable air conditioners come in a single unit that you can easily move around for room-to-room cooling.

To explain in detail, a portable air conditioner typically comes with four key components:

  1. Fan
  2. Refrigerant
  3. Compressor
  4. evaporator/ condenser coils

Trigger by the built-in thermostat; the internal spinning fan will begin drawing hot air inside the portable AC whenever there is a disparity in the desired room temperature. The evaporator coils will extract the heat and moisture out of the air by cooling the refrigerant. Cool air will then be pushed out, effectively reducing the room temperature and dampness. Through compression and pressurization, the condenser coil will condense the water vapor to create high-pressure gas and vent the heat outside via an exhaust hose. The collected moisture will either be removed with the heat through evaporation or collected into a reservoir that requires emptying.

In general, there are two types of portable air conditioners. The most common one would be a self-evaporative model that automatically evaporates moisture and hot air via an exhaust hose. You will find it in major brands like Avallon, DeLonghi, Honeywell, and Whynter because of the convenience and low maintenance. The bundled window kit allows the exhaust hose to fit perfectly in a traditional size window for proper ventilation. If you intend to connect the exhaust hose through a sliding door, an additional extension kit might be required (separate purchase), or you will have to cover the open gap with styrofoam or board.

The less popular type would be the gravity drain models with or without a condensate pump. Like a refrigerant dehumidifier, connect the hose to a floor drain, and the collected water will slowly drip away due to gravity. With a condensate pump, you can connect the hose upwards like towards a sink, and the pump will draw the water out without relying on gravity.

The cheapest and least popular portable AC is those that come with a water tank. During condensation, water extracted out will drip down to the collection tray, and you will have to empty it from time to time. It is inconvenient, and you will have to keep the water tank clean to avoid the growth of microbes.

The Downside With Portable Air Conditioners

A portable air conditioner can be bad for you for many reasons. It is bulky and will take up some floor space, unlike most air conditioners that are mounted to the wall. To install the exhaust hose, you will need to position it close to a window or any ventilation source. Portable air conditioners are also noisy even when idle due to the constant spinning fan. Perhaps most critically, the cooling range is limited to a small room. You need additional units to cover the entire floor, which will add up to the cost.

At this point, I’m sure you have more questions related to portable air conditioners. Here are the common inquiries that we routinely receive on our website to bring you up to speed.

Do Portable Air Conditioners Require Maintenance?

Like all AC, portable air conditioners require regular maintenance to prevent the evaporative/ condenser coils from getting dirty and reduce the cooling efficiency. Dirty particles will clog the coils and prevent the refrigerant from absorbing the heat from the indoor air. The underpressure compressor usage life could also reduce due to overload and overheating. To ensure your portable air conditioner is in tip-top condition, here are some essential maintenance tips you can follow:

  • Before performing any cleaning, switch off and unplug the portable air conditioner to protect yourself from electric shock or fire hazards risk.
  • Clean the AC air filter every 1-4 weeks, depending on how dirty your indoor air is. Gently vacuum the trapped dust and debris to avoid tearing the filter. Use mild soap and lukewarm water to rinse away stubborn particles. Remember to shake off the water and let it room dry completely before inserting the filter back into the portable AC.
  • Regularly wipe the air ventilation grill to prevent dust particles from creating an airflow blockage. While you’re at it, clean the exterior with a damp cloth and keep it as dust-free as possible.
  • If the portable AC comes with a water bucket (non-self-evaporate), empty the water bucket when the beeping sound or whenever it is full. Also, regularly clean the collection tray to prevent mold growth.
  • When not using the cooling device for an extended period of time e.g. during the winter, store the portable AC unit in a cool and dry place. The last thing you need is a mold-infested unit that is completely unusable.
  • Investigate whenever there is a weird sound from the device that is previously unheard of. Rectify it before it causes more damage.

Is It Possible To Extend The Exhaust Hose On A Portable Air Conditioner?

No, you should not extend the exhaust hose that came with your portable air conditioner. It is specifically designed for the particular unit to run safely and efficiently. When you lengthen the hose, the portable AC will not cool effectively, and you are at risk of voiding the manufacturer’s warranty.

Do Portable Air Conditioners Work Without A Window?

A portable air conditioner can work without a window as long as you connect the exhaust hose outside to transfer the hot air out of the room. We have seen portable AC that connects a hose through a hacked wall, drop ceiling, up a chimney, dryer vents, and even a pet door. Granted the exhaust hose is not modified; feel free to improvise.

What Is The Difference Between A Single Hose And Dual Hose Portable Air Conditioners?

Portable air conditioners come with either one exhaust hose or two in the back of the unit. A single-hose portable AC removes heat and cools the air from the room but may create a negative pressure environment. A dual-hose portable AC cools the room by bringing outdoor air in and exhausting indoor air out without creating negative pressure.

In terms of cooling efficiency, dual-hose portable air conditioners are more effective at cooling larger spaces than single-hose variants due to the quicker air exchange process. However, dual-hose units will cost more and drain more electricity.

Can I Use A Portable Air Conditioner In More Than One Room?

It is possible, but it would depend on your portable AC unit’s size and cooling capacity. You will also need to ensure all doors are open so the cool air can travel across the room. Note that the size and distance of the room will significantly affect the AC cooling efficiency. A smaller room will cool much faster than a larger room. We recommend placing the portable AC as centrally as possible so all rooms will receive consistent air cooling.

Do You Have To Put Water In A Portable Air Conditioner?

There is no need to put water in a portable air conditioner with an exhaust hose. Rather, some portable AC requires you to empty the collected water in the reservoir on a weekly basis. Only a ventless air conditioner requires you to put water in the reservoir in order to expel mist that cools down the room.


What Features To Look For In A Portable Air Conditioner?

All not portable air conditioners are created equal. If you are in the market for one: consider looking into the below features that resonate with you.

  • Auto Mode - Relying on the built-in thermostats, the AC will automatically turn on and off the compressor to match the desired temperature you set. A must-have feature.
  • Oscillation - Allows air vents to swing sideways so cool air can be distributed more evenly. Another must-have feature.
  • Dry/ dehumidify mode - Remove excess moisture from the air without affecting the room temperature. Ideal for a damp room with a relative humidity level above 50%.
  • Timer - Allows you to set a timer to switch on/ off the air conditioner. A common feature that should not be overlooked.
  • Fan Mode - Rely solely on the spinning fan to cool the air. Not a critical feature.
  • Remote control - Remotely operate the AC in the comfort of your bed or chair. A convenient feature that is limited to premium models.

Final Thoughts

By the end of this guide, you should have a clearer idea of how portable air conditioners work in cooling a room. To recap, portable air conditioners work the same way as most AC but use slightly different smaller components. You get the perks of better maneuver flexibility at a more approachable price. Conversely, you will have to compromise on the cooling effectiveness. Consider getting a portable air conditioner:

  • You want to move the AC around the house for room to room air cooling.
  • You want a cheap air conditioner with no upfront installation cost.
  • You don't mind the weaker cooling output compared with a conventional AC.
  • You don't mind the bulkiness that will eat up some floor space.

Let's not forget that portable AC requires free space, preferably close to a window and a dedicated 115/ 120 volt power outlet. If a portable AC fits your bill, pick the most reputable brand and sizes according to your room size. Stay safe and keep it cool!

Max Fernandez

A loving father and a dedicated reviewer for airfuji.com with more than 1000 air purifiers under his belt. Max Fernandez is also one of the million patients currently suffering from asthma. Feel free to nudge him if you have any questions.