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Smallest Air Conditioners: Top Compact Cooling Options for 2024

Discover the best small air conditioners, including portable, window & mini-split options. Compare costs & find the right unit for your home!

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In the heat of summer, finding relief in a home or apartment without central air conditioning can quickly become a costly endeavor. Finding the smallest and most efficient AC unit for your space then becomes a top priority.

We’ll take a look at the smallest air conditioner sizes that can accommodate your space by looking at the physical dimensions of these units, the size of your room and the smallest AC units in terms of their cooling capabilities.

Whether you have a small room to cool, a tight window to work with, or limited space for installation, there’s likely a perfect solution for your situation.

Smallest Air Conditioners: BTUs and Dimensions

Choosing an AC unit begins with assessing its efficiency. Air conditioners are measured using a standard called British Thermal Units, or a BTU rating, which measures your unit’s cooling capacity. The larger the room, the higher the BTU your AC will need to efficiently cool the space. 

Small AC unit mounted on wall with pink flowers in the foreground

In general, a room between 100 to 250 square feet will need an AC unit with 5,000 to 6,000 BTUs. Rooms from 250 to 400 square feet will need between 6,000 and 8,000 BTUs. 

Of course, the higher the BTU the better the unit will be at cooling a room, even if it’s more power than your room requires. But these parameters are a good starting point outlining the minimum BTUs you will need for your space. 

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AC Units for Tight Spaces

If you’re looking to install a small air conditioner in a tight space, you’ll need a compact unit. There are a few types of AC units you can consider as you hunt.

Small window air conditioners have a slim profile and can make these units ideal for tight offices or attics, for example. Portable AC units also come in smaller sizes but are often considered less efficient as some hot air is returned to the room as it works. Battery-powered air conditioners are also an option, although these units will typically drain power quickly and require a new battery or charge. 

Small portable ac unit

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When it comes to window AC units, you can typically find models in the following dimensions and capabilities: 

Model A:

  • Dimensions: 14.2″ W x 16″ D x 12.8″ H
  • BTU: 5,000
  • Suitable for rooms up to 150 sq. ft.

Model B:

  • Dimensions: 16″ W x 15.6″ D x 12.8″ H
  • BTU: 6,000
  • Suitable for rooms up to 250 sq. ft.

Portable air conditioners are a good option if you want to be able to use them in various rooms or even on the go in hotel rooms or RVs when you travel. These units don’t require permanent installation and can be moved quickly and easily from room to room. You should be able to find these units in the following sizes: 

Model C:

  • Dimensions: 13.5″ W x 13.5″ D x 24.2″ H
  • BTU: 8,000
  • Suitable for rooms up to 300 sq. ft.

Model D:

  • Dimensions: 12″ W x 13″ D x 28.3″ H
  • BTU: 10,000
  • Suitable for rooms up to 350 sq. ft.

Factors to Consider When Choosing a Small Air Conditioner

  • Room Size: Ensure the BTU rating matches the size of the room you intend to cool; too large a unit can waste energy, while too small a unit may not cool effectively.
  • Installation Requirements: Consider the type of installation required (window, floor space, wall-mounted) and whether it aligns with your living situation.
  • Energy Efficiency: Look for units with Energy Star ratings or high SEER ratings to minimize energy consumption and reduce utility bills.
  • Noise Level: Smaller units should ideally operate quietly, especially if they’re intended for bedrooms or home offices.
  • Additional Features: Consider extra features like remote control, programmable timers, smart connectivity, or built-in dehumidifiers that can enhance convenience and comfort.

Cost of Small Air Conditioners

1. Portable Air Conditioners

  • Cost Range: $200 – $600
  • Installation Cost: Minimal, typically DIY.

2. Window-Mounted Air Conditioners

  • Cost Range: $150 – $500
  • Installation Cost: Low, often DIY, or around $50 – $100 if professional help is needed.

3. Ductless Mini-Split Air Conditioners

  • Cost Range: $800 – $2,500 (for small capacity units)
  • Installation Cost: Higher, usually ranging from $500 to $2,000 depending on complexity and the number of units.

Start Shopping

Finding the smallest air conditioner size for your room that fits your needs is the best way to go about efficiently cooling a space. As you hunt, be sure to consider the BTU rating, dimensions, and portability so you can make the best choice for your situation. 

You can also save money with the right unit by qualifying for certain government rebates. Find out more on our HVAC resources page.  

Find the Right Contractor for Your HVAC Project

Whether you’re ready to begin your project now or need some expert advice, our network of contractors are here to help. With a few simple questions, we’ll find the best local professionals for you

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