• Front view of the MRCOOL DIY® 5th Gen 18K BTU Single Zone Mini-Split Air Handler, designed for easy DIY installation and efficient heating and cooling.
  • MRCOOL DIY® 18K BTU Mini-Split with a 25 ft. QuickConnect® pre-charged line set and DIYPRO® cable for simple, vacuum-free installation.
  • MRCOOL DIY® 5th Gen Mini-Split includes a wireless remote control, allowing users to adjust temperature, fan speed, and mode settings with ease.
  • MRCOOL DIY® 5th Gen 18K BTU Mini-Split backed by an industry-leading warranty, including limited lifetime coverage on the compressor.
  • MRCOOL DIY® 5th Gen 18K BTU Mini-Split is ENERGY STAR® certified, offering high efficiency and lower energy costs.
  • MRCOOL DIY® 5th Gen Mini-Split uses R-454B refrigerant, an eco-friendly alternative with lower Global Warming Potential (GWP) than R-410A.
  • DIYPRO® cable included with the MRCOOL DIY® 5th Gen Mini-Split, providing superior durability against outdoor elements and wildlife.
  • The MRCOOL DIY® 18K BTU Mini-Split connects to the SmartHVAC app, enabling wireless control via iOS and Android devices.
  • MRCOOL DIY® 5th Gen 18K BTU Mini-Split backed by an industry-leading warranty, including limited lifetime coverage on the compressor.
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NEW R-454B Refrigerant

MRCOOL DIY® 5th Gen E Star 18,000 BTU Single Zone Mini Split Complete System with 25ft. Line Set 230V, DIY-18-HP-WM-230D25-O

MRCOOL DIY® 5th Gen E Star 18,000 BTU Single Zone Mini Split Complete System with 25ft. Line Set 230V, DIY-18-HP-WM-230D25-O

$2,909.00 USD
$3,577.99 USD $2,909.00 USD
Save $668.99 Sold out
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⭐ ENERGY STAR Certified

⚡ Voltage: 240V

🛠️ DIY Installation

SKUDIY-18-HP-WM-230D25-O-1

TypeComplete System

Refrigerant Type: R-454B

Line Set Length

✅ This item is in stock!

More than 30 available

Estimated Delivery: November 10 – November 12

Based on order date & typical delivery times.
• Orders Typically ship within 2 business days

View full details

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PRODUCT DESCRIPTION

MRCOOL® DIY® 5th Gen 18K BTU Single Zone Mini-Split Air Handler – Powerful, Energy-Efficient Comfort for Your Home

Upgrade your home’s heating and cooling system with the 5th Gen MRCOOL® DIY® 18K BTU Single Zone Mini-Split Air Handler, designed for effortless DIY installation and year-round climate control in spaces ranging from 500 to 750 sq. ft. Engineered for efficiency, this system features advanced inverter technology, eco-friendly R-454B refrigerant, and smart home integration, ensuring superior comfort without the need for professional installation.

Effortless DIY Installation – No HVAC Technician Needed

MRCOOL’s patented DIY® technology allows you to install your system quickly and easily—no special tools, vacuum pumps, or professional expertise required.

✔ DIY® QuickConnect® Line Set – Pre-charged with R-454B refrigerant, enabling a vacuum-free, tool-free installation.
✔ DIYPRO® Cable – Enhances safety and durability, eliminating the need for electrical conduit while providing superior protection against outdoor elements and wildlife.
✔ Step-by-Step Installation Guide & Video Support – Clear, user-friendly instructions to help you install with confidence.

💡 Perfect for homeowners and DIY enthusiasts looking for an affordable, professional-grade HVAC solution!

Eco-Friendly R-454B Refrigerant – Lower GWP, Higher Efficiency

The 5th Gen MRCOOL® DIY® Mini-Split is designed with R-454B refrigerant, an advanced, environmentally friendly alternative to R-410A.

✔ Lower Global Warming Potential (GWP) – Reduces environmental impact while maximizing efficiency.
✔ ENERGY STAR® Certified Performance – Saves energy and lowers utility bills.
✔ Smart Inverter Technology – Adjusts compressor speed for optimal energy savings and quiet operation.

Smart Home Integration – Climate Control at Your Fingertips

Enjoy the ultimate convenience with multiple ways to control your indoor comfort:

✔ SmartHVAC App – Adjust settings via your smartphone (iOS & Android) from anywhere.
✔ Voice Command Compatible – Works with Amazon Alexa & Google Assistant for hands-free control.
✔ Wireless Remote Control – Easily manage temperature, fan speed, and modes.
✔ Follow Me® Function – The remote acts as a personal thermostat, adjusting airflow based on its location.
✔ Dry Mode (Dehumidification) – Removes excess moisture to improve indoor air quality and reduce humidity.

Durability & Long-Lasting Performance

Built to withstand harsh weather conditions, the MRCOOL DIY® Mini-Split is designed for years of reliable performance.

✔ Gold Fin® Condenser – Corrosion-resistant coating protects against salt air, rust, and extreme weather, making it ideal for coastal homes.
✔ Intertek Certified (5031495) – Rigorously tested to meet industry-leading safety and performance standards.
✔ Ultra-Quiet Operation – Experience whisper-quiet heating and cooling, perfect for bedrooms, offices, and living spaces.

Industry-Leading Warranty – Confidence in Every Purchase

MRCOOL backs the 5th Gen DIY® Mini-Split with an unmatched industry warranty, giving you total peace of mind:

✔ Limited Lifetime Warranty on the Compressor
✔ 7-Year Compressor Warranty
✔ 5-Year Parts Warranty

Why Buy from MRCOOL DIY Direct?

As the USA’s most trusted independent MRCOOL dealer, we provide:

✅ Factory-Direct Pricing – Get the best deals on genuine MRCOOL systems.
✅ Fast & Reliable Shipping – Quick delivery across the lower 48 states.
✅ Expert DIY Support – Need help? Our team is here to assist with installation and troubleshooting.

Upgrade to the MRCOOL® DIY® 5th Gen 18K BTU Mini-Split Today!

Enjoy powerful, energy-efficient climate control year-round—all with a true DIY-friendly installation. Order now and experience the easiest way to heat and cool your space! 🚀

SPECIFICATION & DIMENSIONS

 

🛠️ About Our Longer Line Set Options for MRCOOL DIY 5th Gen Mini-Split Systems

At MRCOOL DIY Direct, we understand that every home is different, and that the standard 25-foot pre-charged line set included with MRCOOL DIY systems may not fit every installation. That’s why we offer a range of longer and customizable line set options, making it easier for you to get exactly what you need — without extra hassle or unnecessary parts.

🚀 How Our Line Set Options Work:

  • Standard System:
    Every system from MRCOOL comes factory-bundled with a 25' pre-charged line set and 25' of control wire.

  • Choosing an Alternate Length:
    If you select a different line set length (such as 16', 35', 41', 50', or 75'):

    • Your order will be custom-bundled individually at our warehouse.

    • This process typically adds 1–2 extra business days for preparation and shipping.

    • You will receive the exact pre-charged line set footage you requested — either as a single line set or a combination of two line sets (if needed) to achieve the proper length.

📦 Important Details to Know:

  • Single vs Combined Lengths:

    • 16': Factory 25' is swapped for a 16' pre-charged line set.

    • 35': A single 35' pre-charged line set is provided.

    • 41': Combines your standard 25' line set with an additional 16' line set + supplied coupler + extended control wire.

    • 50': A continuous 50' pre-charged line set is provided with longer control wire.

    • 75': Combines a 25' + 50' pre-charged line set with couplers and 75' of extended control wire.

  • Control Wire Upgrade:
    Any time your line set length exceeds 25', you will receive a new longer control wire matched to the total length.

    We never recommend splicing control wires. These systems are essentially computers — shielded, continuous control cable ensures no interference, no corrosion, and no installation headaches down the road.

🛒 Why Shoppers Trust MRCOOL DIY Direct:

Unlike big-box retailers that sell you a one-size-fits-all kit (and leave you hunting for missing parts), we custom-configure your system so you have everything you need from the start.

  • No extra trips to the hardware store.

  • No guessing which coupler or cable you need.

  • No surprises during installation.

With years of experience specializing in DIY HVAC systems, MRCOOL DIY Direct has earned a reputation as the USA's most trusted independent HVAC dealer.
We are committed to making DIY HVAC installation simple, affordable, and frustration-free — and our custom line set bundling is just one more way we deliver on that promise.

🔧 Need help choosing the right line set length for your project?
Contact our expert team today — we’re here to help you get it done right the first time!

WHAT'S INCLUDED

  • Pre-Charged Line Set

  • Remote Control

  • Communication Wire

  • Wall Sleeve

  • Condenser

  • Air Handler

  • DIY Installation

OPTIONS & ACCESSORIES
MRCOOL Condenser Wall Mounting Bracket for 9K to 18K BTU MrCool Ductless Mini Split System (MB176)
MRCOOL Condenser Wall Mounting Bracket for 9K to 18K BTU MrCool Ductless Mini Split System (MB176)
$89.27
Elite Condenser Pad - 18 In. x 38 In. x 3 In. For Outside Ground Placement of the MRCOOL DIY Condenser
Elite Condenser Pad - 18 In. x 38 In. x 3 In. For Outside Ground Placement of the MRCOOL DIY Condenser
$79.67
Disconnect Switch and Electrical Whip with #8 AWG
Disconnect Switch and Electrical Whip with #8 AWG
$98.87
Rectorseal RSH-50 Surge Protective Device 50kA 96415
Rectorseal RSH-50 Surge Protective Device 50kA 96415
$106.49
MRCOOL LineGuard 4.5-Inch 16-Piece Complete Line Set Cover Kit for Ductless Mini-Split or Central System (MLG450)
MRCOOL LineGuard 4.5-Inch 16-Piece Complete Line Set Cover Kit for Ductless Mini-Split or Central System (MLG450)
$133.43