Variable Refrigerant Flow (VRF) is an energy efficient heating, cooling, and ventilation (HVAC) system which delivers precise temperatures to individually controlled zones. Widely used in Japan and Europe, VRF technology has been slowly introduced in the United States, most readily adopted in hotels, dormitories, office buildings, and other facilities that must meet the comfort requirements of multiple end users.
How Do VRF Systems Work?
Unlike traditional HVAC systems which connect one evaporator to one condensing unit, VRF systems enable one condensing unit to be connected to multiple evaporators which may be individually controlled for the comfort of the occupant. A heat pump VRF system allows for the simultaneous yet independent heating or cooling of zones connected to the same condensing unit.
With any change in temperature, VRFs will vary the flow of refrigerant to multiple zones. While this results in VRFs running more frequently than a traditional system, which turns off or on depending upon the need for cooled air, VRFs use less energy because they operate at varying speeds. This prevents dramatic changes in temperature, reduces system cycling, and lowers energy consumption.
Variable Refrigerant Flow vs. Variable Refrigerant Volume
Japan’s Daikin Industries first designed these systems in the early 80’s, designating them Variable Refrigerant Volume (VRV) systems. As VRV was a term protected by Daikin, subsequent manufacturers, like LG and Mitsubishi, began to use the term Variable Refrigerant Flow (VRF) to signify the same technology.
Advantages of Variable Refrigerant Flow Systems
- Individual controls offer greater comfort to users
- Quieter operation
- Eliminates the need for mechanical rooms
- Reduces energy consumption
- Requires little to no ductwork
Disadvantages of Variable Refrigerant Flow Systems
- Inefficient for spacious facilities like athletic centers or theaters
- Large up-front cost
- May need a separate ventilation system in high humidity climates or high occupancy areas
VRF systems are an excellent option for facilities with multiple zones in which the individual control features can be fully realized. Flow can be reduced to unoccupied spaces, reducing operational costs and furthering sustainability efforts.
VRFs are not right for every facility as there may be concerns with refrigerant lines and ventilation when installing larger systems so if you are considering Variable Refrigerant Flow for your next project, contact a BCH team member for expert advice. With a quick analysis, we can help you to determine whether this innovative mechanical refrigeration technology would reduce operational expenses for facility owners and afford greater comfort to the occupants.
BCH Mechanical has been a trusted name in Florida construction since 1976, delivering innovative design, high quality craftsmanship and excellent customer service. BCH capabilities include HVAC, plumbing, medical gas, piping, sheet metal, LEED, Design/Build, 3D-CAD/BIM coordination, and HVAC service. Visit BCH on the web: www.bchmechanical.com.