Designed with homeowners in mind, the MRCOOL® DIY® 5th Generation 18,000 BTU Ductless Mini-Split makes professional-grade HVAC accessible—no specialized tools or prior experience required. Ideal for spaces up to 800 sq. ft., this high-efficiency 22.5 SEER2 heat pump system provides both cooling and heating with ease.

Thanks to the 25-foot pre-charged QuickConnect® line set, installation is straightforward and safe. The lines are factory-charged with eco-friendly R-454B refrigerant, eliminating the need for vacuum pumps or refrigerant handling. The included DIYPRO® cable offers a more rugged alternative to traditional conduit, shielding electrical connections from weather, pests, and landscaping equipment.

Control is fully integrated and flexible. Operate the system via the included remote control, the SmartHVAC app on iOS or Android, or use voice commands with Amazon Alexa or Google Assistant. For added longevity in coastal or humid environments, the unit features a Gold Fin® anti-corrosion coating that protects against salt air and moisture.

Built-in features such as Dry Mode, Auto mode, programmable Timer, and Auto Restart enhance energy efficiency and everyday convenience. In the event of a power outage, the system resumes its previous settings automatically for uninterrupted comfort.

This unit is backed by one of the best warranties in the industry, including a limited lifetime coverage*, 7-year compressor warranty, and 5-year parts warranty. Engineered for DIY installation and long-term reliability, the MRCOOL® 5th Gen 18k Mini-Split is a powerful investment for total home climate control.

Key Features

• True DIY Installation – No specialized tools or HVAC experience required. Pre-charged QuickConnect® line set simplifies setup.

• High Efficiency Performance – Rated at 22.5 SEER2 and 11.5 HSPF2-4, offering year-round comfort with energy savings.

• Smart Control Integration – Control the system via remote, SmartHVAC app (iOS/Android), or voice with Amazon Alexa and Google Assistant.

• Gold Fin® Corrosion Protection – Extends the life of the condenser, especially in coastal or humid environments.

• Durable DIYPRO® Cable – Replaces traditional conduit, offering weather- and pest-resistant protection.

• Follow Me® Function – The remote senses temperature at your location for personalized comfort.

• Dry Mode – Reduces excess humidity and improves indoor air quality.

• Auto Restart – Automatically restores previous settings after power outages.

• Advanced Timer & Auto Modes – Set schedules and let the unit automatically maintain desired room temperatures.

• Backed by Industry-Leading Warranty – Includes a limited lifetime warranty, 7-year compressor warranty, and 5-year parts warranty.

Specifications

• Brand: MRCOOL®

• Series: DIY 5th Generation

• Product Type: Single-Zone Ductless Mini-Split

• Voltage: 208–230V, 1 Phase, 60 Hz

• SEER2 Rating: 22.5

• EER2 Rating: 13.7

• HSPF2-4 Rating: 11.5

• HSPF2-5 Rating: 8.5

• Cooling Capacity: 18,000 BTU

• Heating Capacity: 18,000 BTU

• Coverage Area: Up to 800 sq. ft.

• Compressor Type: Rotary

• Fan Speeds: Variable

• Refrigerant Type: R-454B (pre-charged)

• Refrigerant Volume: 44.80 oz

• Line Set Length: 25 ft.

• Liquid Line Size: 1/4"

• Suction Line Size: 1/2"

• Max Line Set Length: 98.4 ft.

• Air Handler Dimensions (WxDxH): 42.52” x 8.90” x 13.19”

• Air Handler Weight: 35.49 lbs

• Air Handler Noise Level (Hi/Mi/Lo/Si): 54.5 / 44.5 / 40.5 / 30.5 / 19.0 dB(A)

• Condenser Dimensions (WxDxH): 35.04” x 13.46” x 26.50”

• Condenser Weight: 93.48 lbs

• Condenser Noise Level: 58.5 dB(A)

• Control Options: Remote, SmartHVAC App, Amazon Alexa, Google Assistant

• Low Ambient Cooling: Down to 5°F

• Certifications: UL Listed, ETL Listed, Energy Star Certified, AHRI Certified

• Warranty:

  • Parts: 5 Years

  • Compressor: 7 Years

  • Extended Limited Lifetime Replacement: Available with MRCOOL® Care Program registration

• Extended Limited Lifetime Replacement: Available with MRCOOL® Care Program registration

• Environmentally Friendly: Yes – R-454B low-GWP refrigerant

• Auto Restart: Yes

• Dry Mode: Yes

• Timer Function: Yes

• Indoor Display: Yes

• Indoor Unit Finish: Glossy white

• Warranty Registration Required: Yes

BTU Size Chart

Which BTU rating should I choose?

• The appropriate BTU rating depends on the size of the space you need to heat or cool.
• A higher BTU indicates greater heating and cooling capacity, allowing the air handler to effectively condition larger areas.

*Ceiling height, insulation quality, and local climate can all affect the actual coverage area. For instance, an uninsulated space will need more BTUs to maintain comfort compared to a well-insulated room.

Shipping & Returns

Shipping Policy

• Free Shipping on All Orders – We provide free standard delivery on all orders within the contiguous U.S.

• Ground Shipping for Smaller Items – Accessories and lighter products ship via standard ground carriers such as FedEx, UPS, or similar.

• Freight Delivery – Large items (HVAC/Heaters) ship via LTL freight. Drivers deliver to the curbside only; they cannot bring items into your home or garage.

• Tracking Information – Tracking is typically provided within 3–5 business days after your order is placed.

• Carrier Updates – Once tracking is issued, allow 1–2 business days for the carrier to populate shipment details.

• More Information – Full details can be found on our Shipping Policy page.

Return Policy

• 30-Day Return Window – Return requests must be submitted within 30 days of delivery; requests after this period cannot be accepted.

• Inspect Upon Delivery – Visible damage must be noted on the driver's paperwork. Report all damage within 24 hours to qualify for a replacement.

• Return Condition Requirements – Items must be unused, uninstalled, and in original packaging, including all boxes, crates, or pallets.

• Restocking Fees – Restocking fees of 25–35% apply to most brands; see full policy for details.

• Non-Returnable Items – Accessories, small components (remotes, line sets), and custom-finish items are non-returnable.

• Full Details – See our Return & Refund Policy page for complete guidelines.