Central air conditioning system consists of cold and heat source system and air conditioning system. The principle of liquid vaporization refrigeration is used to provide the required cooling capacity for the air conditioning system to offset the cooling load of the indoor environment. The heating system provides heat for the air conditioning system to offset the heat load of the indoor environment. The refrigeration system is a vital part of the central air conditioning system. Its type, operation mode and structural form directly affect the economy, efficiency and rationality of the central air conditioning system in operation. The central air-conditioning system needs to use steam coils for heating or cooling, which is one of the air radiators we hold up. It is generally composed of copper tubes wrapped around copper strips.