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 11,800 BTU Through the Wall Air Conditioner is designed for those needing to cool a space up to 530 square feet, such as a bedroom, living room, or apartment. With a cooling capacity of 11,800 BTUs, it offers robust cooling performance. One of its notable strengths is its energy efficiency, with an EER of 10.6, which means it effectively cools while saving on energy costs.

Additionally, it uses R-32 refrigerant, which is more environmentally friendly compared to older refrigerants. The unit is designed specifically for through-the-wall installation, so it won’t fit standard windows, but its universal design means it is compatible with most wall sleeves, adding to its versatility. The product dimensions are 24 inches wide, 20.1 inches deep, and 14.4 inches high, so it’s important to check if it fits your existing wall sleeve or the space you plan to install it in.

In terms of noise, it operates at 66 decibels, which might be noticeable but isn't overly disruptive for most users. The unit offers three cooling speeds and three pre-programmed modes - Energy Saver, Dry, and Cool - providing flexibility based on your needs. Additional features include a remote control for convenience, a washable and reusable filter, insulation foam, and a trim kit for a clean indoor installation. However, it is worth noting that despite its energy efficiency, this model is not Energy Star certified. It also weighs 76 pounds, which might make installation challenging without assistance.

The LG 9,800 BTU Through-the-Wall Air Conditioner with Supplemental Heat is designed for rooms up to 440 square feet, such as bedrooms or offices. It offers both cooling and heating functions, making it versatile for different weather conditions. With multiple fan speeds, users can customize airflow efficiently. The unit includes convenient features like a digital control panel, remote control, and auto-restart after power failures.

Its 4-way air deflection enhances flexibility, and it comes with a filter light reminder, trim kit, and washable filter for ease of maintenance. The unit's Seasonal Energy Efficiency Ratio (SEER) of 9.8 is not particularly high, indicating that it may not be the most energy-efficient option. Additionally, it operates at a noise level of 54 dB, which might be noticeable in quieter settings.

It requires a 230-volt outlet and is relatively heavy at 70 pounds, which could make installation challenging. Despite these drawbacks, its ability to cool medium-sized rooms effectively and additional heating feature make it a practical choice for users seeking a multi-functional air conditioning solution.