"A REVIEW OF VARIABLE REFRIGERANT FLOW SYSTEM AN EMERGING TECHNOLOGY IN HVAC"

The Variable Refrigerant flow technology is rising as the advanced and promising option to the conventional systems. The concept of the VRF has been generated since the early 1990s the general idea behind that was the system should operate on one large outdoor unit and will have several indoor units. Variable refrigerant flow (VRF) is a multi-split air-conditioning system configuration where there is one outdoor condensing unit and multiple indoor units are present. The arrangement of this system can provide the zonal comfort and simultaneous heating and cooling. This technology uses the smart integrated controls, variable speed drives (VSD), refrigerant piping and heat recovery to provide more thermal comfort in the less energy consumption. The variable refrigerant flow control is the key to many advantages as well as the major technical challenge of VRF system. The conventional refrigerant systems turn OFF or ON completely in response to one central controller, whereas the VRF systems continually adjust the flow of refrigerant to each indoor evaporator. Hence the variable refrigerant flow system is providing the energy and space-saving solution to the existing system