MRCOOL DIY 5th Gen Mini Split - 4-Zone 36,000 BTU Ductless Air Conditioner and Heat Pump Condenser with 18K + 12K + 9K + 6K Wall Mount Air Handlers - DIY5-4Z-36HP-18K12K9K6K

MRCOOL DIY 5th Gen Mini Split - 4-Zone 36,000 BTU Ductless Air Conditioner and Heat Pump Condenser with 18K + 12K + 9K + 6K Wall Mount Air Handlers - DIY5-4Z-36HP-18K12K9K6K

Take control of your home’s comfort with the MRCOOL® 5th Gen DIY® Multi-Zone Mini Split System — the ultimate solution for efficient, customizable, and true DIY-friendly heating and cooling.

This powerful 36K BTU 4-Zone system includes one 18K, one 12K, one 9K and one 6K wall mounted air handlers.

Features

• Customize mini-split system: choose the perfect line set length for each zone just above the “Add to Cart” button.
• Ultra-Efficient Cooling & Heating: Enjoy up to 23 and 9.9 HSPF2-4 for energy-efficient year-round comfort.
• DIY-Friendly QuickConnect® Installation: No vacuuming or professional tools needed — pre-charged line sets make setup fast and simple.
• Smart Voice & App Control: Full control via SmartHVAC app, Alexa, Google Assistant, or included wireless remote.
• Eco-Conscious Refrigerant: Uses R-454B refrigerant with a low environmental impact.
• Industry-Leading Warranty: Includes 5-year parts, 7-year compressor, and lifetime replacement with MRCOOL® Care registration.

What our Experts Think

• Powerful 4-Zone System: 36,000 BTU condenser with 18K + 12K + 9K + 6K air handlers delivers efficient heating and cooling for multiple rooms.

• Custom Comfort Control: Each zone operates independently, letting you fine-tune temperatures for every space.

• DIY-Friendly Installation: Designed for homeowners to install easily without professional help.

• Quiet & Energy-Efficient: Inverter technology ensures silent performance and lower energy use.

• Smart Connectivity: Works with mobile apps for remote operation, scheduling, and monitoring.

• Durable & Reliable: Corrosion-resistant condenser ensures long-lasting performance in all climates

Q&A

Q: What type of system is the MRCOOL DIY5-4Z-36HP-18K12K9K6K?
A: It’s a 4-zone ductless mini split air conditioner and heat pump from MRCOOL’s 5th Generation DIY Series, designed for energy-efficient heating and cooling across multiple rooms.

Q: What indoor air handlers come with this configuration?
A: This system includes one 18,000 BTU, one 12,000 BTU, one 9,000 BTU, and one 6,000 BTU wall-mounted air handler, ideal for efficiently conditioning four separate spaces.

Q: Is installation truly DIY-friendly?
A: Yes. The MRCOOL DIY system uses pre-charged Quick Connect line sets that allow homeowners to install the unit without special HVAC tools or professional help.

Q: Does it work for both heating and cooling?
A: Absolutely. The system operates as both an air conditioner and a heat pump, providing year-round climate control even in colder temperatures.

Q: Can each zone be controlled separately?
A: Yes. Each air handler operates independently with its own remote and smart control options via the MRCOOL SmartHVAC app, as well as Alexa and Google Assistant compatibility.

Q: What makes the 5th Gen model different?
A: The 5th Gen MRCOOL DIY features upgraded efficiency, quieter operation, advanced refrigerant technology, and improved Wi-Fi connectivity for a more user-friendly experience.

Maintenance Tips

• Clean air filters monthly — Rinse each indoor air handler’s filter with lukewarm water and let it dry completely to ensure steady airflow.

• Dust indoor units regularly using a soft cloth to keep vents clear and efficient.

• Inspect outdoor condenser coils every 3–6 months and remove dirt, leaves, or debris gently.

• Maintain 24 inches of clearance around the condenser for optimal airflow and cooling efficiency.

• Flush condensate drain lines every few months with a mild vinegar solution to prevent clogs and odors.

• Check refrigerant line insulation annually for cracks or sun damage to ensure proper performance.

• Use “Fan Only” or self-cleaning mode after heavy use to dry coils and prevent mold growth.

• Monitor system operation through the MRCOOL SmartHVAC app for real-time performance and alerts.

• Distribute cooling across all zones to prevent overworking the 18K or 12K units.

• Schedule annual professional servicing to inspect refrigerant pressure, wiring, and overall system condition.