Ultimate Refrigeration & Air Conditioning Dual inverter systems modulate the indoor airflow at the same time as the refrigerant flow to maintain a consistent sensible heat ratio throughout the entire operating envelope. DC 180 degree Sine Wave inverter is used for refrigerant flow control and a permanent magnet electronically commutated motor is used for indoor airflow control. Livezi dual inverter systems control all three comfort drivers: Temperature, Humidity and Velocity.