Bosch15 seer true inverter heat pump condensers deliver maximum efficiency while keeping sound levels to a minimum. The outdoor compressor and motor can freely ramp up and down per demand, offering operating levels from 25-110% and up to 15.5 SEER efficiencies. Your BOVA-24HDN1-M15G condenser consistently monitors room temperature, humidity and refrigerant levels which can drastically decrease energy consumption. A 10 Year Parts Warranty is also included with every Bosch unit installed in a residential application. This an all be achieved while using any 2 Heat / 1 Cool thermostat or better.