MrCool DIY 5th Gen 2 Zone 18000 BTU Mini Split Heat Pump System - Choose Your Indoor Units - R454B

MRCOOL DIY® 18,000 BTU 3-Zone Ductless Heat Pump Condenser – Model DIY-MULTI3-18HP230D-O | 230V

Compact, energy-efficient multi-zone comfort for up to three rooms

The MRCOOL DIY® Multi3 18,000 BTU Multi-Zone Condenser supports up to three indoor air handlers, making it perfect for small homes, apartments, or offices. Designed for compatibility with MRCOOL DIY® Wall Mount and Ceiling Cassette Air Handlers, it delivers quiet, inverter-driven heating and cooling with easy installation using pre-charged Quick Connect line sets.

With a compact footprint, Wi-Fi control, and high-efficiency performance, the DIY-MULTI3-18HP230D-O offers flexible comfort without the need for professional installation.

Features & Benefits

• 18,000 BTU cooling and heating capacity
• Supports up to three indoor air handlers
• 230V operation with variable-speed inverter compressor
• Quick Connect pre-charged line sets for easy DIY installation
• Smart control via MRCOOL SmartHVAC app, Alexa®, and Google Assistant®
• Quiet operation and high SEER2 efficiency rating

MRCOOL DIY® Wall Mounted Air Handlers

Easy-to-install comfort for every room with MRCOOL’s DIY® mini-split technology

The MRCOOL DIY® Wall Mounted Air Handlers deliver exceptional comfort, energy efficiency, and convenience for homes and businesses alike. Available in sizes from 6,000 BTU to 36,000 BTU, these wall-mounted indoor units are designed for use with MRCOOL’s innovative DIY® Ductless Mini-Split Heat Pump Systems. Each air handler offers quiet operation, advanced control options, and easy, no-vacuum installation with the MRCOOL® pre-charged line sets.

Built for DIY installers and professionals alike, these units feature variable-speed inverter technology for precise temperature control, built-in Wi-Fi for smart home integration, and a sleek, modern design that fits comfortably in any space. The washable filters, auto-restart function, and multiple fan modes make maintenance simple while maximizing year-round comfort.

Features & Benefits

• Available in 6,000 to 36,000 BTU capacities to fit rooms of any size
• Designed exclusively for MRCOOL DIY® Ductless Mini-Split Heat Pump Systems
• Easy wall-mounted installation – no vacuum pump or special tools required
• Built-in Wi-Fi for smart home control via the MRCOOL SmartHVAC app, Alexa®, and Google Assistant®
• Variable-speed inverter technology ensures energy-efficient performance
• Quiet operation for enhanced comfort in bedrooms, offices, and living areas
• Washable, reusable filters reduce maintenance costs
• Auto restart and sleep mode for convenience and energy savings
• Factory-approved components for reliability and long service life

MRCOOL DIY® Ceiling Cassette Air Handlers Multi-Zone Ductless Mini-Split Systems

Discreet, powerful comfort for every room — easy to install and built to last

The MRCOOL DIY® Ceiling Cassette Air Handler Series offers premium, built-in comfort for homes and businesses without the need for complicated installation. Designed exclusively for use with MRCOOL DIY® Multi-Zone Ductless Mini-Split Heat Pump Systems, these ceiling-mounted units combine sleek design, whisper-quiet operation, and the industry’s easiest setup — all while delivering powerful heating and cooling performance.

Available in 6,000 BTU, 9,000 BTU, 12,000 BTU, and 18,000 BTU capacities, MRCOOL DIY® Ceiling Cassettes provide flexible, zoned comfort for spaces ranging from small bedrooms to large open living areas. Each model installs seamlessly between standard ceiling joists, maintaining a clean, low-profile appearance that blends into any room design. With built-in Wi-Fi connectivity, users can control temperature settings through the MRCOOL SmartHVAC app, or hands-free via Alexa® and Google Assistant®.

Engineered with inverter-driven technology and four-way directional airflow, these ceiling cassette air handlers distribute air evenly and efficiently across your space. The result is customized comfort, energy savings, and professional-quality performance — all achievable without professional installation costs.

Features & Benefits

• Available in 6,000 – 18,000 BTU models for rooms up to 750 sq. ft.
• Compatible with MRCOOL DIY® Multi-Zone Mini-Split Heat Pump Systems
• Ceiling-mounted design installs between standard joists for a sleek, flush appearance
• Four-way directional airflow ensures consistent comfort throughout the room
• Built-in Wi-Fi control via the MRCOOL SmartHVAC app, Alexa®, and Google Assistant®
• Inverter technology delivers quiet, energy-efficient performance
• Simple DIY installation — no vacuum pump or special tools required
• Ideal for residential or light commercial applications
• Factory-backed reliability from MRCOOL, a trusted name in home comfort innovation

Fast nationwide fulfillment from the USA. Free shipping on qualifying orders over $1,500. See our shipping and returns policy for full details.