10 Best Wall AC Units 2025 in the United States

The MRCOOL 9000 BTU Easy Pro Series mini split is a solid choice if you're looking for a ductless air conditioner that also provides heating, making it useful all year round. Its 9,000 BTU cooling capacity is well-suited for spaces up to about 400 square feet, such as small rooms or offices. The unit runs at a noise level of 43 dB, which is relatively quiet but you might still notice it in very quiet environments. The energy efficiency rating is 2 stars, which means it works fairly well but won’t be the cheapest to run compared to more efficient models.

One of the big advantages is its DIY-friendly installation, designed so homeowners can set it up without professional help, which can save money and hassle. It also includes helpful features like a timer, refrigerant leak detection, and an air cleaning system with easy-to-clean filters to keep indoor air fresh.

Considering its capabilities, this MRCOOL model is a practical pick if you want a dependable, versatile unit that can handle both cooling and heating for smaller spaces and prefer easy installation, although the 2-star energy rating and moderate noise level may be factors to keep in mind.

The MRCOOL 24000 BTU Ductless Inverter Mini Split is a solid choice for cooling and heating spaces up to about 1,050 square feet, making it suitable for medium-sized rooms in homes, offices, or small commercial areas. With its 24,000 BTU capacity, it provides strong cooling power, and the included heat pump means you can use it year-round for both comfort and convenience. It runs at a relatively quiet 43 decibels, which is gentle enough for most living or working environments. The unit has a 2-star BEE rating, indicating moderate energy efficiency; it might not be the most economical option in terms of power use but should be reasonable for regular use.

Installation is user-friendly since it’s part of MRCOOL’s DIY Easy Pro Series, designed for easier setup compared to traditional split systems, and maintenance is simplified with features like easy-to-clean filters and a refrigerant leakage detector, helping keep the unit running smoothly and indoor air quality fresh thanks to its Active Clean Technology. The unit measures around 33 inches wide and 21 inches high, so it’s a relatively large wall unit, requiring adequate space for installation.

While it covers cooling and heating well, individuals looking for the highest energy efficiency or the quietest operation might find better options elsewhere. This unit offers a balanced combination of power, convenience, and basic energy considerations for users needing a reliable all-in-one heating and cooling solution without complex installation.

The COSTWAY 9000BTU Mini Split Air Conditioner & Heater is designed for cooling and heating rooms up to about 450 square feet, making it a solid choice for medium-sized bedrooms, offices, or small living spaces. Its 9000 BTU cooling capacity suits typical room sizes in this range, providing reliable temperature control. With a high 19 SEER2 rating, this unit is energy efficient, which means it can keep your energy bills lower compared to less efficient models. It uses the eco-friendlier R32 refrigerant, which has a lower environmental impact than older refrigerants.

Noise level is quite low at 42 decibels on the quietest setting, so it won’t be disruptive during sleep or work. The unit offers versatile airflow options with 4 wind speeds and 4D auto swing, helping to distribute air evenly for better comfort. Installation requires a professional since it is a mini-split system, which may add to the initial cost and effort but ensures proper setup and performance. Maintenance is made easier by a self-cleaning function that helps keep the air fresh and reduces manual cleaning. Extra features like multiple operating modes (cool, heat, dry, fan, sleep, ECO) and a 24-hour timer add convenience and customization.

The unit’s 115V power requirement might limit placement options in some homes, and professional installation can be more expensive compared to window units. This mini-split AC is a good fit for those looking for an energy-saving, quiet, and versatile wall-mounted unit for medium rooms, as long as they are comfortable with the need for professional installation and the associated initial setup costs.