10 Best Thru Wall Ac Units 2025 in the United States

The COSTWAY 12000BTU Mini Split Air Conditioner & Heater is a versatile unit designed for both cooling and heating spaces up to 750 square feet. With a high Seasonal Energy Efficiency Ratio (SEER) of 20.0, it promises excellent energy efficiency, which can lead to lower utility bills. The unit operates relatively quietly at 51 dB, which is generally considered acceptable for residential use, ensuring it won't disrupt your peace and quiet significantly.

The included remote control and multiple modes (auto, cool, dry, heat, and fan) provide flexibility and convenience for year-round comfort. The self-cleaning feature at high temperatures and auto-defrost function contribute to maintaining air quality and system longevity. However, installation must be done by a licensed HVAC installer, which could add to the initial cost and complexity. Additionally, the product uses R32 refrigerant, which is more environmentally friendly but might require specific inquiries about its availability for future maintenance.

With a robust warranty covering parts for 5 years and the compressor for 8 years, this unit offers long-term reliability. Potential buyers should consider the installation requirements and ensure compatibility with their existing setup. This unit is ideal for those looking for an energy-efficient, multi-functional air conditioning solution for medium-sized rooms.

The Keystone 12,000 BTU through-wall air conditioner is designed to cool medium-sized spaces up to 550 square feet, making it suitable for bedrooms, nurseries, or bathrooms. With a solid cooling capacity of 12,000 BTUs, it efficiently manages temperature and includes a built-in dehumidifier that removes about 2.3 pints of moisture per hour, helping improve comfort on humid days. In terms of energy use, it has an Energy Efficiency Ratio (EER) of 10.5, supported by energy-saving modes like 'Energy Saver' and 'Sleep' that help reduce electricity bills without compromising comfort.

The noise level sits at around 56.5 decibels, which is average for this type of unit—noticeable but not overly loud for most rooms. Installation requires mounting through a wall, which keeps your window space free and maintains a clean look inside, though some effort is needed to fit it properly using the included trim kit. The unit also comes with a smart remote control that measures the room temperature and adjusts settings accordingly every few minutes, making it easy to use.

Additional helpful features include adjustable airflow louvers, programmable timer, and a filter light reminder to keep maintenance on track. The unit’s weight at over 78 pounds means installation may require assistance. Though it doesn’t have a star energy rating, its combination of features and reasonable energy efficiency make it a solid choice for those seeking a reliable, quiet, and space-saving air conditioner for moderately sized rooms.

The Keystone 10,000 BTU Through the Wall Air Conditioner is designed for those seeking a reliable cooling solution for small to medium spaces up to 450 square feet. With a cooling power of 10,000 BTUs, it efficiently manages indoor temperatures and doubles as a dehumidifier, removing about 2.3 pints of moisture per hour. Its energy efficiency is supported by an EER, though not Energy Star certified, it offers energy-saving modes like 'Energy Saver' and 'Sleep' to help minimize electricity costs.

Installation is straightforward with a universal trim kit, making it a good choice for maintaining window views and floor space. The included remote control, which measures room temperature and adjusts accordingly, adds a layer of convenience, particularly with its programmable timer and adjustable air louvers. However, at 57.4 dB, its noise level might be noticeable, especially in quieter settings like bedrooms or nurseries.

The Keystone 10,000 BTU AC unit is suitable for those prioritizing effective cooling with added dehumidification in a through-wall installation, making it ideal for apartments or small homes. Its user-friendly features make it accessible, though potential buyers should weigh its noise level and energy efficiency against their personal needs. The durable build and 5-year warranty (1 year for parts and labor, plus 4 additional years for the sealed system) provide peace of mind. However, the substantial weight of 68.2 pounds could be a consideration during installation or if moving the unit is necessary.