10 Best Through-The-Wall Air Conditioners 2026 in the United States

The Keystone 18,800 BTU Window-Wall Air Conditioner is a versatile unit that is well-suited for cooling and supplementally heating large spaces up to 1,000 square feet. With a substantial cooling capacity of 18,000 BTUs and a supplemental heating capacity of 16,000 BTUs, it can provide year-round comfort. However, it's important to note that the heating function is meant to supplement rather than replace primary heating sources, particularly when outside temperatures range between 23°F and 76°F.

This unit also offers dehumidification and fan-only modes, adding to its utility. The I Sense remote is a smart feature that ensures consistent comfort by regularly transmitting room temperature readings to the unit for accurate cooling adjustments. For energy-conscious users, the 'Energy Saver' and 'Sleep' modes can help reduce electricity bills, although it's worth mentioning that the unit is not Energy Star certified. Measuring 25.39 x 23.62 x 17.91 inches, it fits well in standard wall sleeves and comes with a window installation kit for flexibility. At 55 dB, the noise level is moderate, which might be a consideration for those sensitive to sound.

Additional features like a filter light reminder and a 4-way swing enhance convenience and airflow control. Despite its weight of 117.3 pounds, installation is manageable with the included kit. Its Seasonal Energy Efficiency Ratio (SEER) of 10.7 might be on the lower side compared to other models. The Keystone unit comes with a 1-year parts and labor warranty, plus an additional 4 years for the sealed system, offering peace of mind for potential buyers. This air conditioner is a strong contender for those needing reliable cooling and supplemental heating for larger rooms, though its noise level and lower energy efficiency might be points to consider.

The LG 10,000 BTU Through the Wall Air Conditioner is designed for efficient cooling of spaces up to 440 square feet, making it suitable for bedrooms, living rooms, and small apartments. With an Energy Efficiency Ratio (EER) of 10.7, it offers decent energy savings, although it doesn't have an Energy Star certification. The unit includes a remote control and features three cooling speeds, three pre-programmed modes, and a turbo fan for versatile cooling options.

The Energy Saver mode adds a layer of efficiency by maintaining the desired temperature with minimal energy use. Its installation is straightforward with a plastic trim kit and protective mesh grille, although it’s only suitable for wall installation, not for windows. The air conditioner runs at 60 dB, which is moderately noisy and might be noticeable in quieter environments.

Additional features include a washable, reusable filter, insulation foam, and a dehumidifying capacity of 2.9 pints per hour, which is useful for humid climates. While its dimensions (24 x 20.1 x 14.4 inches) and weight (77 pounds) may require some effort during installation, the unit's performance and ease of use make it a solid choice for those looking for a reliable wall-mounted air conditioner. Potential buyers should consider the noise level and ensure their wall setup is compatible with this unit.

The BLACK+DECKER 18,000 BTU air conditioner is designed to cool spaces up to 1,000 square feet, making it a solid choice for larger rooms or small apartments. Its cooling power is strong enough for whole floors or living areas that need reliable temperature control. The unit offers four cooling levels including an auto mode, plus a fan-only setting, allowing easy adjustment of comfort levels. It includes a remote control featuring useful options like sleep mode, an energy saver, and a 24-hour timer, which can help reduce electricity use.

This air conditioner has a Seasonal Energy Efficiency Ratio (SEER) of 11.8, indicating moderate energy efficiency that balances performance with reasonable power consumption. Noise-wise, it produces about 54.5 decibels, which is noticeable but typical for air conditioners of this size—you might hear it in quiet rooms but it is not overly loud. Installation is flexible with options for window or through-the-wall mounting; the unit comes with a wall sleeve and mounting parts, though professional installation is recommended for through-the-wall setups due to wiring requirements. Its dimensions (around 25 by 24 by 18 inches) fit standard double-hung windows and typical wall openings, but measuring your space beforehand is advised to ensure compatibility.

The unit includes a one-year warranty for labor and parts, except for the compressor which has a five-year warranty, offering standard coverage. Customer reviews are generally positive, with a solid 4.2-star rating, reflecting good performance for many users. This BLACK+DECKER air conditioner presents a dependable option for strong cooling in larger spaces and offers convenient features like remote control and multiple modes, while delivering moderate noise levels and standard energy efficiency.