MRCOOL DIY® 5th Generation Single-Zone Ceiling Cassette Mini Split System

This MRCOOL DIY® 5th Generation ceiling cassette mini split is built for homeowners who want reliable heating and cooling without cluttering their walls or paying for professional installation. The recessed ceiling design keeps the unit out of the way while delivering even airflow across the room, making it a strong fit for bedrooms, living rooms, home offices, finished garages, workshops, or open-concept spaces.

This system is offered in an 18,000 BTU configuration and runs on standard 208/230V power. Under normal insulation and layout conditions, it is sized to handle spaces up to about 750 square feet, making it a practical choice for single-room or open-area climate control.

What sets this system apart is true DIY installation. The pre-charged Quick Connect® line set arrives sealed from the factory with R-454B refrigerant already inside. There is no need for vacuum pumps, refrigerant gauges, brazing, or HVAC certification. Connections are made with basic hand tools, allowing capable homeowners to install the system on their own schedule and avoid contractor costs.

The ceiling cassette spreads air evenly in all directions, eliminating hot and cold spots common with wall-mounted units. Temperature and mode adjustments can be handled with the included remote or through the MRCOOL SmartHVAC app. Voice control support through Amazon Alexa and Google Assistant is available for those who want hands-free operation, but the system works just as well without relying on smart features.

Designed for dependable year-round use, the system provides full heating performance down to -5°F and continues operating in temperatures as low as -13°F. Cooling remains stable in outdoor temperatures up to 122°F, making it suitable for hot summers and cold winters alike. Dry Mode helps reduce excess humidity, which is especially useful in basements, garages, and humid climates.

Warranty coverage reflects long-term reliability. The system includes a 7-year compressor warranty and a 5-year parts warranty, with the option to extend to a limited lifetime compressor warranty by enrolling in the MRCOOL Care auto-ship program.

What’s Included

- DIY® 5th Gen outdoor condenser, factory charged with R-454B

- DIY® 5th Gen indoor ceiling cassette

- 25 ft pre-charged Quick Connect® line set

- Communication wire and drain hose

- Remote control and WiFi dongle

This system is a solid choice for homeowners who value function over flash, want clean installation, and prefer to do the work themselves while still getting dependable, modern heating and cooling.

📄 Single Zone Specs 📄 Multi Zone Specs 📄 Ceiling Cassette Specs

MRCOOL DIY Mini Split Sizing Guide

Which air handler is best for your room size?

The size of your room is the main factor in choosing the right unit. MRCOOL DIY 4th Gen comes in various sizes, each designed to cool and heat specific square footage ranges.

Here's a quick reference for choosing the right BTU based on your room size:

• 6,000 BTU covers up to 250 square feet
• 9,000 BTU covers up to 350 square feet.
• 12,000 BTU covers up to 550 square feet.
• 18,000 BTU covers up to 800 square feet.
• 24,000 BTU covers up to 1,050 square feet.
• 36,000 BTU covers up to 1,500 square feet.

How BTU Limits Work in Your Mini-Split System

You can opt for high BTU air handlers for strong heating and cooling. But, if you plan to run multiple air handlers at the same time, consider the main unit's (condenser) maximum power.

Here’s the deal: Suppose your condenser can handle 18,000 BTU, and you have two indoor air handlers, each at 12,000 BTU. If both run simultaneously, they’ll automatically adjust to 9,000 BTU each to match the condenser's limit. This ensures the system runs safely.

If you usually run one air handler at a time, a lower BTU condenser might be sufficient. But if you plan to use all air handlers together, a higher BTU condenser is the way to go. This lets you enjoy the full power of each air handler without overloading the system.

By considering these factors, you can ensure your MRCOOL DIY 4th Gen unit is perfectly sized for your needs, keeping you comfortable year-round.

For personalized assistance or further clarification, please feel free to contact our customer support via chat or call. Our team is ready to help you make the best choice for your cooling needs.

DIY Multi-Zone Manuals

MRCOOL DIY Mini Splits Warranty

MRCOOL distributor (hereinafter “Company”) warrants this product against failure due to defects in materials or workmanship under normal use and maintenance as follows:

• Standard Warranty: 5-year parts warranty and 7-year compressor warranty.
• Limited Lifetime Compressor Warranty: Available if specific conditions are met.

Conditions for Limited Lifetime Compressor Warranty:

• Registration: The unit must be registered at the following web address: https://mrcool.com/warranty within 60 days of the installation date.

• MrCool Care Program Enrollment: The original, registered owner must enroll in the MrCool Care program within 4 months from the installation date. This program requires a biannual fee and includes a DIY cleaning kit for regular maintenance.

• Regular Maintenance: The unit must be cleaned biannually using the MrCool Care kit as part of the preventative maintenance to ensure proper function throughout its lifespan.

Coverage Details:

• Within the First 7 Years: If compressor failure occurs, verified by diagnostic testing performed by a certified HVAC technician, the warranty provides one entire unit replacement (equipment only).
• After 7 Years: The limited lifetime compressor warranty covers the cost of a replacement compressor (equipment only).

Important Notes:

• The warranty does not cover any costs incurred for diagnosis or replacement of equipment.
• If the original owner does not register the unit, the warranty defaults to the standard 5-year parts and 7-year compressor warranty.
  
  

📑 DIY Multi-Zone Brochure

📑 Quick Start Setup Guide

📑 Installation Owner's Manual

📑 Performance Specification

📑 Troubleshooting Solution Guide

📑 Remote Control User Manual

📑 Ceiling Cassette Manual

📑 Ceiling Cassette Specification

📑 Warranty Statement

📑 Multi-Zone AHRI Certifications: 18K BTU - 27K BTU - 36K BTU - 48K BTU

📑 Multi-Zone Energy Guide Certifications: 18K BTU - 27K BTU - 36K BTU - 48K BTU