10 Best Air Conditioners Air Conditioners 2026 in the United States

The LG 18,000 BTU Heat and Cool Window Air Conditioner is designed for medium to large rooms up to 1,000 square feet, making it a solid choice if you need effective cooling and heating in a single unit. With an 18,000 BTU cooling capacity, it can handle fairly large spaces, which is convenient if you want to avoid buying separate devices for different rooms. It also includes a supplemental heating option, so it can keep you comfortable year-round, not just during hot months.

The unit is WiFi-enabled and works with Amazon Alexa and Google Assistant, allowing easy remote control via your phone or voice commands — a handy feature if you like smart home devices. Its energy efficiency ratio (SEER) is 11.1, which is decent but not the highest available, so expect moderate energy consumption. Noise level is around 57 decibels, which is noticeable but typical for a powerful window AC; it won’t be completely silent but shouldn’t be too disruptive either.

Additional conveniences include a filter light reminder, a 24-hour timer for scheduling, and an auto restart function that turns the unit back on after power outages, so you don’t have to reset settings. The unit is relatively large and heavy at 126.5 pounds, which might make installation a bit challenging without help. It also comes with only a 1-year warranty, which is standard but something to keep in mind if you're looking for long-term coverage. This LG window air conditioner is well-suited for users seeking a versatile cooling and heating solution for bigger rooms who appreciate smart controls and can tolerate moderate noise and energy use.

The Daikin Oterra Series 24,000 BTU mini-split is a strong choice for cooling and heating spaces up to about 1,500 square feet. With a cooling power of 22,400 BTU (variable between 7,000 and 26,400 BTU) and heating capacity up to 23,600 BTU, it offers flexible temperature control thanks to its DC inverter technology. Its high energy efficiency is notable, boasting a 21 SEER2 rating and excellent EER of 12.0, which means it uses less electricity while keeping your space comfortable year-round. This makes it a smart pick for those wanting to save on energy bills while staying cool or warm.

The unit works well in a wide range of temperatures, from freezing cold to hot, making it suitable for different climates and various rooms like basements, sunrooms, or garages where traditional ACs aren't practical. It includes features like an anti-corrosion heat exchanger, automatic defrost, and a washable air filter, which help the system last longer and keep air quality high. The package comes ready with installation parts and a remote control, simplifying setup.

If you are looking for an energy-efficient, versatile ductless solution with strong heating and cooling abilities, the Daikin Oterra is a solid option, especially for medium-sized rooms and homes aiming for comfort and savings.

The Frigidaire 12,000 BTU Window Air Conditioner is designed to cool medium to large rooms, up to about 550 square feet, making it a good fit for living rooms, larger bedrooms, or small offices. Its 12,000 BTU cooling capacity is effective for this space size, providing enough power to keep the area comfortable. The unit operates quietly at around 57 decibels, which is about the noise level of a normal conversation, so it won’t be too disruptive when running. It offers three fan speeds and 6-way directional airflow, allowing you to customize the cooling to your liking. Energy efficiency is decent, with a Seasonal Energy Efficiency Ratio (SEER) of 10.9, and features like Eco Mode and Sleep Mode help lower electricity use by adjusting cooling as needed. This can save money on energy bills if used properly.

The air conditioner also includes helpful features such as a washable dust filter with a light reminder for cleaning, a remote control for easy operation, and a 24-hour timer to match your schedule. It even has a Dry Mode to reduce humidity, which can improve comfort on muggy days. Installation is straightforward since it is a window unit, but keep in mind it weighs about 63.5 pounds, so some effort is needed to mount it securely. One limitation is the relatively short 1-year manufacturer warranty, which might be a concern for long-term reliability. While 57 dB is quiet for an AC, it’s not whisper silent, so very noise-sensitive users might notice it. This model delivers solid cooling performance with convenient energy-saving and comfort features, making it a practical choice for those seeking a reliable window air conditioner for medium-sized spaces.