10 Best Windowless Air Conditioners 2025 in the United States

The SereneLife 3-in-1 Portable Air Conditioner is a solid choice for anyone needing a compact cooling solution without window installation. Its 8,000 BTU cooling power is suitable for rooms up to about 215-350 square feet, making it a good fit for bedrooms, small living rooms, or home offices. It offers three modes—cooling, dehumidifying, and fan—adding versatility beyond simple air conditioning, which helps reduce humidity and allergens. The unit is equipped with an exhaust hose and rolling wheels, so it’s portable and easy to move around, though it does weigh about 46 pounds. Noise level is moderate at around 55 dB, which might be noticeable in very quiet environments but generally won’t disrupt daily activities.

The energy efficiency is average, with a 2-star BEE rating and a SEER of 9.8, so it won’t drastically impact your electricity bill but isn’t the most efficient option available. Water drainage is handled by the dehumidifier function, removing about 1.2 liters per hour, making it convenient for humid climates. Controls are user-friendly, including a digital touch panel and remote control, which simplifies operation. However, it’s on the bulkier side for portability and might not cool very large spaces effectively.

This model includes a 1-year warranty, providing some peace of mind. While it is not the quietest or most energy-efficient in its class, it serves well as a portable, easy-to-use air conditioner with extra features like dehumidifying and fan modes for small to medium rooms.

The SereneLife Small Air Conditioner offers a 10,000 BTU cooling capacity, which is suitable for cooling rooms up to around 300 square feet rather than the 450 sq ft mentioned, making it a good choice for smaller spaces like bedrooms or small living areas. It is a portable unit with a free-standing design and rolling wheels, plus a window exhaust kit, so it can be moved and set up relatively easily. The noise level is moderate at 57 decibels, which is comparable to a normal conversation—noticeable but not overly disruptive.

Energy efficiency is average with a SEER rating of 2.6, meaning it won’t be the most economical option for heavy use. This model includes a built-in dehumidifier that removes moisture at a rate of 1.2 liters per hour, which helps improve indoor air comfort and may reduce allergens. The unit also offers three operating modes (cooling, fan, and dehumidifier) and features WiFi connectivity and a remote control, making it convenient to adjust settings without getting up.

The size (around 28 x 13 x 12 inches) is fairly compact for a portable AC, but it weighs 55 pounds, so while movable, it’s somewhat heavy. Air filtration and 4-way swing vents help circulate and mildly purify the air. The cooling coverage is slightly overstated in the description, and the energy efficiency could be better if you plan to run it for long periods. This product represents a solid option if you want a portable, easy-to-use AC that also reduces humidity, best suited for smaller rooms and moderate cooling needs.