In public buildings, energy consumption of air conditioning accounts for 40%~-60% . Decreasing energy consumption of air conditioning and developing highly efficient and energy-saving products are the aim of refrigerating and air conditioning technology. Multiıconnected air-conditioning unit is a new type system developed under these circumstances. It was analyzed experimentally the performances of variable refrigerant flow systems for heat recovery unit of multi-connected air-conditioning, the characteristic of load and the relationship between heat transfer property and refrigerating capacity were discussed