Mr. Cool Advantage 12,000 BTU 21.2 SEER2 Wall Mounted Heat Pump System (115V) - R454BMRCOOL A 12 HP WMAH 115D O & A 12 HP C 115D O Advantage 5th Gen 12,000 BTU 115V R 454B Ductless Mini Split Heat Pump System (Air Handler + Condenser) The MRCOOL A 12 HP WMAH 115D O & A 12 HP C 115D O Advantage 12k BTU 115V delivers efficient, quiet, year round comfort for rooms up to 550 sq ft. Using eco friendly R 454B (80% lower GWP than R 410A), this ductless system achieves up to 21. 2 SEER2 and 8. 7 HSPF2 4 to reduce energy use and costs. Built