4 Best Through Wall Air Conditioning Units 2026 in the United States

The Keystone 14,000 BTU Wall Mounted Air Conditioner is a solid choice for cooling and supplemental heating in large rooms up to 700 sq. ft. Its impressive 14,000 BTU cooling capacity ensures efficient temperature control, while the 10,600 BTU supplemental heating capacity offers versatility for year-round use, though it should not be relied on as the primary heat source. One of its strengths is the smart remote control, which adjusts cooling based on the room temperature, adding convenience to its operation. Additionally, its energy-saving modes like 'Energy Saver' and 'Sleep' can help reduce electricity bills.

However, its Seasonal Energy Efficiency Ratio (SEER) of 9.3 is on the lower end, indicating it may not be as energy-efficient as some other models. Moreover, this unit is not Energy Star rated, which could be a consideration for those prioritizing high energy efficiency. In terms of noise level, it operates at 61.5 dB, which is relatively quiet for its capacity but may still be noticeable in quieter settings.

The installation is straightforward with the included trim kit, and it requires a 230V/20-amp outlet, which may necessitate additional electrical work if not already available. The unit’s dimensions (20.3 x 24.2 x 14.5 inches) are typical for through-wall air conditioners, ensuring compatibility with most wall sleeves. Additional features like the dehumidifier and filter light reminder enhance its functionality. The Keystone 14,000 BTU wall AC is well-suited for large living areas, offering powerful cooling and heating with practical bonuses, though its energy efficiency might be a drawback for some users.

The OLMO 8,000 BTU Through-the-Wall Air Conditioner is a versatile unit that offers both cooling and heating options, making it suitable for year-round use in residential, commercial, and hotel settings. With a cooling capacity of 8,000 BTUs and a heating capacity of 4,200 BTUs, it is designed to efficiently manage the temperature in medium-sized spaces. The unit operates on 115 volts and comes pre-charged with R-32 refrigerant, which is more environmentally friendly compared to older refrigerants.

The included wall sleeve simplifies installation, and the dimensions (20.28"D x 24.21"W x 14.53"H) ensure compatibility with standard wall openings for through-the-wall units. The noise level is reasonably low at 52 dB, which is comparable to a normal conversation, making it suitable for living areas and bedrooms. However, it is not Energy Star certified, which implies it may not be the most energy-efficient option available. The unit can be controlled via a digital panel with LED display, a remote control, or a compatible wireless smartphone device, adding a layer of convenience.

Weighing 80 pounds, it may require assistance during installation. Additionally, its WiFi capability allows for remote operation, which can be a significant advantage for tech-savvy users. This unit would be particularly beneficial for those looking for a reliable and versatile climate control solution that offers modern features like remote and WiFi control.

The Keystone 12,000 BTU window-wall air conditioner is a solid choice for cooling medium-sized rooms up to 550 square feet. It offers a balanced cooling capacity that can handle larger living rooms or apartments comfortably. One of its strengths is the supplemental heating feature, which provides extra warmth when temperatures are mild, though it’s not designed to replace your main heating system. The unit's energy efficiency is decent, with a Seasonal Energy Efficiency Ratio (SEER) of 10.9, which helps keep electric bills reasonable, especially if you use the energy-saving and sleep modes.

In terms of size, its dimensions (about 19" deep, 21.5" wide, and 14.6" high) make it compatible with typical window or wall sleeves, and it includes a window installation kit to simplify setup. Noise level is moderate at 55 decibels—comparable to a quiet conversation—so it may be noticeable but not overly disruptive in daily use. Additional features like a remote with a room temperature sensor, 4-way air swing, dehumidifier, and filter reminder add convenience and comfort.

On the downside, the supplemental heating is limited to certain outdoor temperature ranges, and some users might find the noise level a bit high for bedrooms or very quiet spaces. The warranty covers parts and labor for one year, with extended coverage for the sealed system, giving some peace of mind. This unit is well-suited for those needing a reliable and multifunctional window or wall air conditioner that balances cooling, heating, and dehumidifying in medium-sized rooms without breaking the bank.