? Seasonal Energy Efficiency Ratio; a measure of cooling efficiency for air conditioners and heat pumps. The higher the SEER, the more energy efficient the unit. Energy efficiency... unit. The evaporator is connected to the condensing unit by copper tubing and electrical wiring which is passed through a 2 3 hole. Basically, it is a small central air unit... with the flexibility of cooling or heating one room or more; zoning. What are the advantages of installing a Fujitsu ductless mini-split over a central air system? 1) With Central Air you...