MRCOOL DIY 4th Gen vs 5th Gen Mini Splits: What’s New and Which One Should You Choose?

MRCOOL DIY mini split systems are ductless heat pumps designed to heat and cool homes without the need for professional installation. With pre-charged lines and a straightforward setup process, both the 4th Gen and 5th Gen models offer efficient, zone-based climate control, surpassing the capabilities of traditional HVAC systems.

As a home comfort solution, MRCOOL DIY mini split systems ensure stable climate control performance with the 4th Gen, while the 5th Gen adds higher efficiency, lower noise levels, and improved smart controls. These updates improve temperature stability, HVAC energy savings, and overall system performance for everyday residential use.

Understanding the MRCOOL DIY Mini Split Series

The MRCOOL DIY series is a line of ductless heat pump systems designed to simplify installation while providing year-round heating and cooling for residential applications. Unlike traditional mini-split systems that often require professional refrigerant handling and specialized HVAC equipment, the DIY lineup utilizes pre-charged Quick Connect® line sets to reduce installation complexity.

The series is available in multiple configurations, including:

• Single-zone systems for individual rooms and dedicated spaces

• Capacity options ranging from 9,000 BTU to 36,000 BTU

• Systems designed for both cooling and heat pump operation

• Models suitable for spaces ranging from approximately 375 to 1,550 square feet

The MRCOOL DIY lineup has evolved to accommodate changing efficiency standards, refrigerant requirements, and installation technologies. These developments have resulted in differences between the 4th Gen and 5th Gen systems in areas such as refrigerant platforms, efficiency ratings, installation components, and warranty coverage.

Ready to install a ductless heating and cooling system? Explore MRCOOL DIY mini-split systems, including pre-charged Quick Connect® line sets, air handlers, condensers, installation accessories, and HVAC replacement parts at PartsHnC. Enjoy fast shipping delivered directly to your doorstep. 

MRCOOL DIY 4th Gen Features and Performance

The MRCOOL DIY 4th Gen mini split is a ductless heat pump for residential heating and cooling. It uses DC inverter technology for efficient, demand-based temperature control. Key features and performance details are listed below.

1. BTU Capacity and Performance Coverage: The 4th Generation lineup is available in capacities ranging from 12,000 BTU to 36,000 BTU, providing coverage for spaces from up to 500 square feet to up to 1,500 square feet. All models utilize DC inverter variable speed technology, 4-way airflow, and single-zone operation.

• 12K BTU (1 Ton): Up to 500 sq. ft. coverage, 305.88/211.76/147.06 CFM airflow, 37/31/23.5 dBA

• 18K BTU (1.5 Ton): Up to 750 sq. ft. coverage, 465.29/361.76/304.12 CFM airflow, 44.5/37/31 dBA 

• 24K BTU (2 Ton): Up to 1,000 sq. ft. coverage, 605.88/505.88/364.71 CFM airflow, 48.5/43.5/33 dBA 

• 36K BTU (3 Ton): Up to 1,500 sq. ft. coverage, 673.53/502.94/367.65 CFM airflow, 52/45/34  dBA

2. Installation and System Design: All MRCOOL DIY 4th Generation mini-split systems use a pre-charged Quick Connect® line set that eliminates the need for vacuum pumps, refrigerant charging, or specialized HVAC tools. Each setup is a single-zone system that includes a wall-mounted indoor air handler and an outdoor condenser. 

3. Smart Control and Connectivity: Wi-Fi connectivity is included across the lineup through the SmartHVAC app, allowing remote control from Apple and Android devices. The systems also support Amazon Alexa and Google Assistant voice commands. Specifications include:

4. Operating Modes: Standard operating modes include Auto, Cool, Heat, Fan-Only, Dry, and Sleep. The Follow Me function uses the temperature sensor in the handheld remote to adjust operation based on the temperature at the user's location within the room.

5. Gold Fin Coating: An anti-corrosive overlay on the exterior condenser that protects the coils against salty coastal air or high humidity. 

What’s New in the MRCOOL DIY 5th Gen Mini Split?

The MRCOOL DIY 5th Generation series introduces updates to refrigerant technology, efficiency standards, installation design, and warranty coverage. It retains the DIY installation approach of previous generations while incorporating changes that meet current HVAC requirements and performance standards.

1. R-454B Refrigerant Platform: The most significant change is the transition from R-410A to R-454B refrigerant. This refrigerant has a lower Global Warming Potential (GWP) than R-410A, helping the 5th Generation lineup align with current environmental regulations while supporting efficient heating and cooling operation.

2. Updated Efficiency and Capacity Range: Unlike the 4th Generation lineup, which primarily relied on SEER, EER, and HSPF ratings, the 5th Generation systems are rated using SEER2, EER2, and HSPF2 performance standards.

The lineup is available in capacities ranging from 9,000 BTU to 36,000 BTU, providing coverage for spaces from approximately 375 square feet to 1,550 square feet.

• 9K BTU (0.75 Ton): Up to 375 sq. ft. coverage, 54 dBA

• 12K BTU (1 Ton): Up to 550 sq. ft. coverage, 54 dBA

• 18K BTU (1.5 Ton): Up to 800 sq. ft. coverage, 58.5 dBA

• 24K BTU (2 Ton): Up to 1,000 sq. ft. coverage, 58.5 dBA

• 36K BTU (3 Ton): Up to 1,550 sq. ft. coverage, 60.5 dBA

These performance ratings provide a more accurate representation of real-world efficiency and energy consumption under current testing standards.

3. Reinforced DIYPRO® Installation Technology: The 5th Generation series introduces the reinforced DIYPRO® cable, eliminating the need for electrical conduit during installation. Combined with the pre-charged QuickConnect® line sets, it reduces installation steps and component requirements.

4. Enhanced Warranty Coverage: The DIY 5th Generation lineup includes a 7-year compressor warranty and a 5-year parts warranty. Additional limited lifetime replacement coverage is available through the MRCOOL Care Program for qualifying systems.

Explore the top 9 benefits of MRCOOL DIY heat pumps you should know before buying.

MRCOOL DIY 4th Gen vs 5th Gen: Side-by-Side Comparison

Both generations retain DIY installation, inverter operation, and smart controls, but the 5th Gen adds key upgrades in refrigerant technology, efficiency, installation components, capacity, and warranty. The details below highlight the mini split comparison:

Summary: Which MRCOOL DIY Mini Split Is Right for You?

Choosing between the MRCOOL DIY 4th Gen and 5th Gen depends on whether you prefer a proven platform or the latest upgrades. The 5th Gen adds R-454B refrigerant, updated efficiency standards, and DIYPRO® technology, while the 4th Gen remains a reliable option for homeowners seeking established performance and R-410A compatibility. 

Key Takeaways

• The 5th Gen replaces R-410A with R-454B refrigerant to meet current HVAC refrigerant standards.

• A 9K BTU option expands the 5th Gen lineup for smaller room applications.

• The reinforced DIYPRO® cable eliminates the need for a separate electrical conduit during mini split installation.

• Maximum coverage increases from 1,500 sq. ft. in the 4th Gen to 1,550 sq. ft. in the 5th Gen.

• The refrigerant transition prevents compatibility between 4th Gen and 5th Gen system components.

• Installation technology, refrigerant platform, and warranty coverage are the primary differences between the two generations.

FAQs

What is the life expectancy of a MRCOOL mini split?

With proper maintenance, a MRCOOL mini split can typically last 15 to 20 years. Factors such as usage patterns, installation quality, and routine servicing can influence its lifespan.

Can I install a MRCOOL DIY 5th Gen mini split without professional help?

Yes. The DIY 5th Gen series is designed for homeowner installation and includes pre-charged QuickConnect® line sets and a DIYPRO® cable to simplify the process.

Is it worth upgrading from a MRCOOL DIY 4th Gen to a 5th Gen system?

Upgrading may be worthwhile if you want R-454B refrigerant, updated efficiency standards, DIYPRO® installation technology, and enhanced warranty coverage. However, a properly functioning 4th Gen system can still provide reliable heating and cooling performance.