MRCOOL 2 Zone 36K BTU (12K+18K) 23 SEER2 Ductless Heat Pump DIY 5th GenCool or heat large zones with whisper quiet performance, smart control, and a DIY install that skips the HVAC tech. The MRCOOL DIY Multi Zone 36,000 BTU Dual Zone Mini Split delivers powerful climate control to two large roomswithout hiring a contractor. With one 12K air handler (for up to 550 sq ft) and one 18K (for up to 800 sq ft), its ideal for open spaces, primary bedrooms, or converted garages. This system comes pre charged with R 454B