How Do Portable Air Conditioners Work? – Beginner’s Guide

| Last Updated: July 9, 2021

This guide will explain how a portable air conditioner works to cool a room.

These ACs are both cooling-effective and energy-efficient and work on a similar basis to a standard refrigerator. Their main functions are cooling and the removal of humidity from a room. 

We will look at the more technical aspects and guide you to the effective use of these units.

Portable Air Conditioner Terminology and Common Concepts

This section will explain the terminology used in this article and discuss a portable air conditioner’s main components. 

Thermodynamics: A law of physics stating that heat naturally flows from warm to cold. If you want the hot air to flow from cold to warm, this process will need additional external forces. The process is also known as refrigeration.

Extract: This is the process where the air conditioner pulls the warm air from indoors and vents it outside.

Vent: Venting is the expulsion of warm air to the outside after extraction from inside the room. This process is also known as exhausting the hot air outside.

Refrigerant: Also known as coolant, this toxic substance, made up of CFCs, absorbs the heat inside the room and vents it outside.

Single-hose: A single-hose is a basic air conditioner design. It uses an air compressor to power the cooling system by extracting warm air indoors and venting it outdoors.

Dual-hose: A dual-hose design uses separate hoses for extraction and venting processes. This process is more efficient than a single-hose unit.

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British Thermal Units

BTUs: This stands for British Thermal Units and is used to measure an air conditioner’s cooling capacity. The primary standard measure is 20 BTU per square foot that requires cooling. 

Compressor: This compressor raises the temperature and pressure of the refrigerant. It enables the process of moving heat from inside the room to the condenser.

Condenser: This component of the unit circulates the air over the coil to allow for heat transfer.

Coils: AC units come with components called an evaporator coil and a condenser coil. The evaporator coil absorbs heat from inside the room and can usually be found attached to the inside of the air handler. The condenser coil works together with the evaporator coil in the heat exchange process, thereby producing cool air. 

Dehumidification: This process decreases humidity levels inside. This helps to improve the level of comfort inside.

How Do Portable Air Conditioners Work?

Portable air conditioners are cooling-effective, easy-to-use options for cooling purposes. They require minimal installation and they are capable of cooling many areas as they are easy to move from room to room when equipped with wheels, which many are. 

Their primary function is cooling, but they are also effective dehumidifiers. Different types of ACs have different dehumidification processes. These include self-evaporation, gravity-drain, and the manual removal of water.

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  • Self-Evaporating Process -This process applies to the more advanced units that evaporate moisture collected automatically during cooling, along with the warm air. 

  • Gravity-Drain Process – By attaching a drain hose to the drain port, water is directed to a relevant outlet.

  • Manual Removal – Many units come with trays or buckets, where water collects during the cooling process. These need regular emptying.

How do portable air conditioners work? The cooling process is based on thermodynamic principles. It extracts heat from a room and vents it outside. A suitable window or door must accommodate a single, large exhaust hose that moves the hot air outside. Window kits are supplied with the unit, and all that remains is to plug the unit in and switch it on.

It is essential to select the correctly sized unit for your space. Units that are too small or too large for the room will be ineffective as they will either not cool effectively or run up large energy bills. The higher the BTU, or cooling power, of an air conditioner, the larger the area it can cool. 

They work by extracting warm air from inside the room and pulling it inside the unit. This heat is then vented outside through the hose, while the air is cooled and vented back into the room with the moisture extracted.

To do so, we require three main components, namely the fan, refrigerant, and compressor.

How Does the Fan Work?

The fan extracts hot and humid air from the room. The condenser coils cool the hot air. At the same time, water vapor is condensed on the coils. It is essential to keep the coils clean, or proper cooling might be disrupted.

What Does the Refrigerant Do?

The extracted hot air is transferred to the refrigerant in the coils, which heats up and becomes a high-pressure gas moving through the system.

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The air’s moisture is removed via either a self-evaporative system or a water tray that must be regularly emptied.

What Does the Compressor Do?

The compressor condenses the refrigerant, and the heat generated is vented outside by use of an exhaust hose.

How Does a Dual Hose Portable Air Conditioner Work?

A dual-hose unit works more efficiently than a single-hose unit as it uses one hose to bring in cool air and the other to vent the warm air. This process prevents the creation of negative pressure, thereby improving cooling and energy efficiency. 

How Long Should a Portable AC Be Left On?

Portable air conditioners are an excellent method of cooling your home. Used correctly, they are both efficient and less energy-consumptive than other types of air conditioners. Although the ideal running time is 15-20 minutes, the following factors will affect this:

  • The hotter it is outside, and the higher the humidity, the longer it will take your unit to reach the desired temperature.

  • The lower the thermostat setting, the longer it will take to reach that temperature.

  • A unit that is too small for the area will take longer to cool said area. 

  • The unit must be well-maintained, with the water tray emptied regularly.

  • The quality of your home insulation is essential. A poorly-insulated room can lead to hot air leaks.

The longer your unit runs, the more energy it utilizes. A well-maintained unit will run efficiently, use less power, and be timed to switch off as the desired temperature is reached.

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Are Portable Air Conditioners a Good Option for Cooling Your Home?

Portable air conditioners are a great option for cooling your home. There are, however, many factors to consider that can affect the efficiency of the unit. It is important to select a correctly sized unit with enough cooling power (BTU) to cool the intended space. It should also be placed in an area with adequate window space and ventilation to vent hot air and humidity.

As these units are mobile, they are convenient for cooling occupied rooms without wasting energy cooling empty rooms. They are energy-efficient and guarantee lower energy bills if used correctly.

Ideal for smaller spaces like living areas, they are easy to install and set to reach an ideal temperature using the thermostat. Many air conditioners also come with remote control and timer, ensuring that your space is cool and ready for you when you come inside from warm exterior temperatures. 

If you wish to ensure the unit’s longevity, you should ensure that it is well maintained. That means regularly emptying the water tray, cleaning the air filter daily, wiping the air vents, and keeping it in a cool, dry area.

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A portable air conditioner is an effective, cost-efficient means of cooling an area. They require a few components to extract warm air into the unit, where it is cooled and vented outside. It also acts as a dehumidifier, removing moisture from the air and venting it outside with the warm air. Easy to move around, these units are a great and efficient way to cool an entire house without a significant increase in utility costs.

People Also Ask

By now, you understand that portable air conditioners work similarly to a standard refrigeration process with a fan, refrigerant, and compressor. These are some frequently asked questions that could assist you when deciding to purchase a unit. 

Do Portable Air Conditioners Work Without a Window?

These units must vent the hot air outside, and most come with an easy-to-install window kit. If there is no suitable window, they can work through a suitable sliding door, a drop ceiling panel, or through wall ventilation.

Do Portable Air Conditioners Need to Be Drained?

Some units come with a condensation exhaust system, but those that come with a water tray should be emptied regularly.

Do You Have to Put Water in a Portable Air Conditioner?

Any unit that uses an exhaust hose does not require water to be added. Portable air conditioners work by extracting moisture from the warm air, which then self-evaporates and collects in the water tray.

What Happens to the Moisture Filtered Out of the Air?

The moisture is either removed through a self-evaporative system, venting the water vapor outside, or is collected in a water tray that must be emptied regularly.

What Size Space Can a Portable AC Effectively Cool?

A unit with 7,000-10,000 BTUs would cool a space of up to 300 square feet. A unit with 11,000-14,000 BTUs would cool a room from between 350 to 700 square feet.

My name is Bob Wells and I am a retired HVAC tech from Washington state. I am currently retired and no longer do much with HVAC, however, I feel like I have a lot of knowledge in the subject and I wanted to create a website where I could talk about what I've learned and help upcoming HVAC techs. Find more info about me and HVAC Training 101.