Use this multi-zone system to heat and cool 4-different spaces in your home or business. The MRCOOL DIY 36k BTU 21.5 SEER 4-Zone Ductless Heat Pump Split System: 9k plus 9k plus 12k plus 12k is one of the only multi-zone systems available that you can easily install yourself without expert HVAC help. The outdoor heat pump powering this system has a heating capacity of up to 36,000 BTU and is highly efficient with a 21.5 SEER rating. This is thanks in part to the variable speed DC inverter. The MRCOOL DIY Ductless Split System is a heat pump by design. So when the appliance heats your home or business, the appliance is reversing the air conditioning process and pulling heat indoors from outside. The two 9,000 BTU air handlers distribute heated and cooled air effectively in spaces up to around 375 sq. ft. The two 12,000 BTU air handlers work best in rooms up to 500 sq. ft. Color: White.