If a summer heatwave overwhelms your home’s air conditioning system, consider a portable air conditioner to provide relief in rooms that need it most. Portable ACs aren’t a substitute for central AC. However, they can come in handy for rarely used spaces, small rooms, upstairs rooms, or any other difficult indoor spaces to keep cool.

The key factors when choosing a portable AC unit for your home are the BTU rating matched to your room size, useful features like programmable timers and remote controls, energy efficiency, proper venting setup, and maintenance requirements.

Read on to learn how to choose the best portable AC to stay comfortable despite the heat. 

Consider Your Cooling Needs

Before shopping, decide which rooms you want to cool and find out their square footage. Portable ACs have a defined cooling capacity in British thermal units (BTUs). Choose a model with a high enough BTU rating for the room size. Undersized units won’t provide adequate cooling, while oversized units will waste electricity.

BTU recommendations:

  • 150 to 200 square feet: 5,000 to 6,500 BTUs
  • 200 to 300 square feet: 6,500 to 8,000 BTUs
  • 300 to 400 square feet: 8,000 to 10,000 BTUs
  • 400 to 500 square feet: 10,000 to 12,000 BTUs

Measure room dimensions and match the BTU rating for optimal performance.

Look for Key Features

Portable ACs offer convenient features beyond basic BTU cooling power:

  • Casters provide mobility.
  • Digital controls allow adjusting the thermostat and timer.
  • Remote controls let you control the air conditioning from across the room.
  • Wi-fi connected models allow control through an app.
  • Different fan speeds adjust airflow when needed.
  • Dehumidifier mode reduces humidity for comfort.
  • Adjustable louvers direct airflow. 
  • Sleep mode to automatically turn off after a set amount of time.

Other handy features include washable filters to maintain performance, auto restart after power outages, and a programmable on/off timer. Compare features when shopping to find useful options for your needs.

Look for Efficient Operation

ac unit
Image Credit: Canva

Focus on ENERGY STAR-certified models, which meet efficiency standards to save electricity and money versus less efficient units. Also, check the Energy Efficiency Ratio (EER). The higher the EER, the more efficient the AC. Take note of the model’s manufacturer warranty.

Units with a programmable timer function to run the AC only when needed lower energy consumption by turning it off while the space is unoccupied.

Understand Venting Needs

You must understand how portable ACs vent hot air outside. This process usually involves a flexible exhaust hose from the unit to a nearby window. Choose a model with an exhaust hose and window venting installation kit. Make sure the hose reaches your window to vent the warm air. Extensions are typically available if needed.

Depending on the design and capacity output, portable AC units may use a single-hose or dual-hose venting configuration. The best portable air conditioner for your space depends on your specific needs. Consider a window air conditioner if you need to save floor space. 

Consider Maintenance

While portable ACs typically require little maintenance, air filters should be cleaned monthly to maintain adequate cooling operation. Depending on your climate and conditions, condenser coils may require periodic cleaning. Be sure to read the owner/maintenance manual. Following the manufacturer’s guidelines is the best way to achieve long-lasting cooling and energy-efficient operation.

Compare Installation Costs

Expect to pay $150–$300 for professional window unit venting for a basic portable AC. Complex venting costs more. DIY installation is free if you are comfortable setting up the exhaust hose and window kit. Exercise caution and always follow the manufacturer’s guidelines. Be sure to factor in installation fees to determine the total cost if you do not plan to install the portable AC unit yourself.

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Shop Smart to Save Money

At major retailers, average prices for portable ACs range from $250–$600. Larger BTU capacities cost more. Look for summer sales on portable ACs with steep discounts. The savings help offset the cost. Buying an efficient ENERGY STAR model also saves on energy bills long-term. The extra efficiency is typically worth the higher initial investment.

Portable AC Purchase Considerations

Limited window access makes venting a portable AC difficult. Consider alternatives like a window AC unit or upgrading your central air conditioning unit or evaporative cooler.

Portable AC units are louder than window air conditioners or central air systems. Research the published decibel ratings before purchasing if you’re concerned about noise levels.

So, Are Portable ACs Worth Buying?

For cooling a single room when required, portable ACs offer flexible relief without renovating your central HVAC system. Units with adequate BTU capacity and venting can sufficiently cool rooms up to 500 square feet. Focus on ENERGY STAR models with good EER ratings, useful features, and proper maintenance. These factors will help you choose the best portable AC to provide comfort on hot days while keeping your electric bill in check.

FAQs About Portable Air Conditioners

How long do portable ACs last?

Portable AC units typically last around 6 to 10 years with regular filter cleaning, periodic maintenance, and adherence to manufacturer guidelines.

Can you run a portable AC with the window closed?

Yes, but in most cases, it is easiest to vent a portable AC unit through the window. If you can’t or don’t want to use a window, you can install a dryer vent through an exterior wall for venting the unit.

Do portable ACs require venting outside?

Yes. Venting the hot air outside is vital for cooling functionality and performance.

What portable AC size do I need?

Match the BTU rating to the space’s square footage. Over or undersized units won’t cool properly.

Can I use one portable AC in multiple rooms?

It’s best to buy units for each room. Open doors between multiple spaces may help cool air in adjacent rooms to some degree, but portable AC units are only designed to cool single spaces.

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Reviewed for accuracy, cost data, industry best practices, and expert advice by Jonathon Jachura.
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Elisabeth Beauchamp

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Elisabeth Beauchamp is a content producer for Today’s Homeowner’s Lawn and Windows categories. She graduated from the University of North Carolina at Chapel Hill with degrees in Journalism and Linguistics. When Elisabeth isn’t writing about flowers, foliage, and fertilizer, she’s researching landscaping trends and current events in the agricultural space. Elisabeth aims to educate and equip readers with the tools they need to create a home they love.

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Jonathon Jachura


Jonathon Jachura is a two-time homeowner with hands-on experience with HVAC, gutters, plumbing, lawn care, pest control, and other aspects of owning a home. He is passionate about home maintenance and finding the best services. His main goal is to educate others with crisp, concise descriptions that any homeowner can use. Jon uses his strong technical background to create engaging, easy-to-read, and informative guides. He does most of his home and lawn projects himself but hires professional companies for the “big things.” He knows what goes into finding the best service providers and contractors. Jon studied mechanical engineering at Purdue University in Indiana and worked in the HVAC industry for 12 years. Between his various home improvement projects, he enjoys the outdoors, a good cup of coffee, and spending time with his family.

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