VRF HVAC Systems in Schools

Posted By: Jason Peck Education , Membership ,
Variable Refrigerant Flow (VRF), also known as Variable Refrigerant Volume (VRV), is an HVAC technology developed and implemented in the early 1980s in Japan. VRF Systems consist of multiple, indoor, low-operating-sound fan-coil units connected to one outdoor condensing unit with a single refrigerant piping circuit. VRF systems control the amount of refrigerant directed to each indoor unit based on its individual demand for cooling or heat. The result is improved energy-efficiency compared to older, one-size-fits-all HVAC systems, greater temperature control in zones or classrooms independent of one another. Compared to most standard water type applications, inverter compressor technology provides more comfort and capacity modulation for part loads within the building utilizing refrigerant instead of inefficient pumps, tower loops with chemical treatment, on/off motors and staged compressors, etc.
Since the piping and equipment for VRF is relatively compact compared to other systems, it may be a good solution for renovating older buildings especially schools where floor-to-floor dimensions and above ceiling space is limited. VRF systems help maintain constant, optimal room temperatures and avoid indoor climate variations that can disturb the learning environment. The VRF technology allows for easy use, ultra-quiet operation and independent temperature control in each classroom or space maximizing indoor air quality and comfort.
The Howard Middle School project came along with its challenges as well as an opportunity to make a mark and do something innovative. Coming up with a system mechanical system that would satisfy the desires of the Owner and provide comfort in a hundred year old, 114,000 sf renovated building and also in the 94,000 sf of modern 2020 additions was one of the design team’s biggest hurdles.
Working closely with the Atlanta Public Schools, the architect, the consulting engineer, the commissioning agent and the construction manager, the team at Daikin Applied Georgia sought to optimize the design to create an installation that would meet the budget and time frame for the Howard Project. The modular design of a VRF system facilitates expedited installation time frames as well as offering the design team a smaller footprint, less impact on the building and lower structural loading than conventional HVAC systems making it ideal for renovating a historic building. The VRF system allows for the reduction or elimination of larger ductwork, as well as related system components like air distribution fans and water pumps.
“The engineering team initially recommended a VRF system for the renovation of the David T .Howard School because of the reduced amount of ductwork required inside the building, allowing the Architects to maintain the high ceilings and large windows of the existing classrooms. A VRF system also reduced the amount of floor space needed for an alternate 4 pipe system, allowing existing space to be used for program space.”
Chris Kloes, PE, CEM, LEED AP, Stevens & Wilkinson, Architects Engineers
“VRF systems yield high savings compared to traditional HVAC systems, which means school systems can expect to save on their utility bills. They can also be used in a wide variety of applications, such as Howard Middle School, which had no central HVAC prior to the renovation. Installation of VRF systems requires minimal modification to the original structure, which saves time and money on design and construction.”
Dick Dutro, CxA, BCxP, CPD, LEED AP BD+C, Total Systems Commissioning, Inc.
There is no perfect system for every application and in some cases, multi-zone high efficiency applications such as VRF are more costly up-front on the installation. More units may also mean more maintenance cost over time, although typically not significantly so and those may be offset by inherently lower utility costs. Components may not be consistently swapped across brands, so it is important to buy a well-known and supported brand as with any type system. Although this technology is becoming more common, not all technicians are versed in maintenance and repair of these systems. VRF itself may not have the same level of humidity management as other systems, but when coupled with a dedicated outdoors air system as in the Howard project will offer one of the best solutions from control, comfort, efficiency and long-term economy.
Daikin Applied Georgia has collaborated on hundreds of K-12 projects in the Georgia market and has developed an understanding of some of the inherent hurdles and challenges within the K-12 community. Daikin welcomed the opportunity to work with Atlanta Public Schools and the project team to make the renovation of the historic Howard Middle School facility a successful sustainable project and a great story to tell.
Daikin is a global leader in the HVAC Industry, providing market-leading product innovation for over 90 years. This commitment to innovation led to the first Variable Refrigerant Flow (VRF) System in 1982 and has been used in the education community since the 1990’s.
Jason Peck is the Field Sales Executive and Business Developer for Daikin Applied Georgia. He has spent the last 10 years of his 27-year career in the HVAC industry with Daikin. For more information he can be reached at jason.peck@daikinapplied.com