The Pioneer Diamante Pro WYT-20S is a versatile, mid-tier ductless mini-split system engineered for stronger performance and broader application versatility, delivering an average 20-SEER efficiency rating. Built for dependable year-round comfort (even in challenging climates) its advanced inverter heat pump maintains stable heating output down to -4°F ambient temperatures. The Pro series uses next-generation R454B refrigerant and is fully compatible with Pioneer’s new 540L wired controller for enhanced professional-grade control in residential or light-commercial installs. With eight capacity options, including dual-voltage availability in the 9k and 12k sizes, the lineup offers flexible solutions for rooms of nearly any size. Every system ships with a complete 16 ft. installation kit and communication cable, ensuring a streamlined and efficient installation from start to finish.