MRCOOL DIY 18,000 BTU 21.2 SEER2 5th Gen Hyper Heat Single Zone Mini Split System - 230V

The MRCOOL DIY 18,000 BTU 21.2 SEER2 5th Gen Hyper Heat Single Zone Mini Split System is built for real winters, keeping full heating capability in outdoor temperatures as low as -22F while covering rooms up to 800 square feet on a 230V circuit.

Cold-climate performance does not complicate the install. The 25 ft pre-charged Quick Connect line set means no vacuum pump, no gauges, and no special tools or refrigerant certification, and the included DIYPRO cable adds protection against weather, animals, and everyday wear. Most homeowners have it mounted and connected in an afternoon.

Ideal Spaces

• Homes in northern states and mountain climates
• Living rooms, master bedrooms, and open areas
• Heated garages and workshops that see hard freezes
• Additions and converted spaces where winter heat matters most

Rated for spaces from about 500 up to 800 square feet, the 18K Hyper Heat holds its output where standard heat pumps fade. As always, insulation quality decides how close you get to the top of that range, and a drafty space will need more margin.

Features

• Heats at -22F: Hyper Heat inverter technology keeps producing heat in temperatures that shut down or cripple conventional heat pumps, so it can work as a primary heat source in cold climates.
• 21.2 SEER2 cooling efficiency: ENERGY STAR certified, with an 11 HSPF2 heating rating that keeps winter operating costs in check.
• 19 dBA indoor low: the wall-mounted air handler is close to silent on its lowest setting, topping out at 54.5 dBA.
• SmartHVAC app plus voice control: Wi-Fi built in, with iOS and Android app support, Amazon Alexa, and Google Assistant, plus an included remote.
• Washable, reusable filter: no recurring filter purchases, just rinse and reinstall.
• Gold Fin condenser coating: corrosion resistance for the outdoor unit, with Auto-Restart, Timer, and Sleep modes on the indoor side.

Key Specs

• Cooling capacity: 18,000 BTU
• Heating capacity: 18,000 BTU, rated operation to -22F
• Efficiency: 21.2 SEER2, 12.5 EER2, 11 HSPF2
• Coverage: up to 800 sq ft
• Power: 208/230V, single phase, 25A max breaker, 19A min circuit ampacity
• Sound level: 19 to 54.5 dBA indoor, 58 dBA outdoor
• Line set: 25 ft pre-charged Quick Connect, extendable to 75 ft max

What you should know

Hyper Heat costs more than the standard 5th Gen 18K, and the premium buys one thing: heating output in extreme cold. If your winters rarely drop below about 20F, the standard 5th Gen unit will serve you just as well for less money. If you regularly see single digits or below zero, this is the model that keeps up.

The system runs on R-454B refrigerant, the current-generation platform, and its line sets and components are not interchangeable with 4th Gen (R-410A) equipment. Electrical needs are modest for the capacity: a dedicated 208/230V circuit with a breaker no larger than 25A and 19A minimum circuit ampacity. The condenser weighs just under 100 lbs, so have help on hand when you set it.

Warranty

• 7-year compressor warranty and 5-year parts warranty with product registration.
• Register your system with MRCOOL after installation to lock in the full coverage.

Specifications:

Need help?

Not sure whether Hyper Heat is worth it for your climate? Call 1-800-514-2418 and we will give you a straight answer. Order online in minutes. Secure checkout, free shipping, and no sales tax.

Good AirX is an Authorized MRCOOL Dealer. Every unit ships new, factory-sealed, and fully covered by MRCOOL's manufacturer warranty.