10 Best Coldest Air Conditioner 2026 in the United States

The Della 36K BTU Quad 4 Zone mini split air conditioner is a powerful and versatile option for cooling large spaces up to 1750 Sq. Ft. It features a high cooling capacity with 36,000 BTU and effectively serves multiple rooms thanks to its four indoor air handlers, which all have separate controls, allowing for individualized climate settings in each room. The energy efficiency is commendable with a SEER rating of 19, and it uses DC Inverter technology, promising up to 30% power savings. This makes it a cost-effective choice in the long run.

Additionally, it is compatible with Alexa, offering convenient control through voice commands and WiFi connectivity for remote access to settings and functions. With its ultra-quiet operation at just 41 dB, it ensures a peaceful environment, which is a significant advantage for residential settings. Multiple fan speeds and smart functions such as 4D airflow, sleep mode, eco energy saving mode, and a 24-hour timer add to its user-friendly design.

However, it’s worth noting that the installation requires professional assistance due to the need for line-set vacuuming and potential adjustments to freon levels, which can be an additional cost. Furthermore, the self-cleaning function indicated in the display is not operational, which might confuse some users. Despite these minor drawbacks, the Della 36K BTU air conditioner reflects its reliability and performance.

The DELLA 28K BTU Tri Zone Mini Split AC is a strong choice if you need cooling and heating for up to three rooms, covering about 1200 square feet in total. It has three indoor units, each with 9000 BTU capacity, which can be controlled separately, giving you personalized comfort in each space. Thanks to its DC inverter technology and a high 20 SEER rating, it is very energy efficient, potentially saving you around 30% on power compared to traditional units. Plus, it works well even in cold weather, down to about 5°F, making it suitable for cold regions.

The system operates quietly at around 41 decibels, which is about the noise level of a quiet library, so it won’t disturb your peace. It also includes useful features such as Alexa compatibility, sleep mode, multiple fan speeds, and a dry mode to reduce humidity. The airflow can be adjusted in four directions for even cooling or heating.

On the downside, the unit does not support a self-cleaning function despite the button appearing on the controller, which means you’ll need to maintain it manually. Installation is complex and requires professional help, so it's not a DIY project. The package includes a full installation kit but keep in mind that any changes to pipe length during installation require refrigerant adjustments, adding to the complexity. This air conditioner is well suited for homeowners looking for multi-room cooling and heating with good energy efficiency and quiet operation, especially in cooler climates. It is less suited for those wanting a simple, self-maintaining system or an easy DIY setup.

The Della 36K BTU Dual Zone Mini Split Air Conditioner is a powerful cooling unit capable of cooling up to 2050 sq. ft. It comes with two indoor handlers of 12,000 BTU and 24,000 BTU each, offering personalized climate control for different rooms. This unit is energy efficient with a SEER2 rating of 19, which means it can save up to 30% on power usage. It operates quietly at 51 dB, making it a good choice for those sensitive to noise.

The air conditioner also includes a variety of smart features like WiFi and Alexa compatibility, multiple fan speeds, 24-hour timer, sleep mode, and eco energy-saving mode. However, it requires professional installation and line-set vacuuming during setup, which might be a downside for those looking for a DIY solution. This product is ideal for anyone looking for an efficient, quiet, and versatile air conditioning solution for large spaces and multiple rooms.