One problem many building managers face is heating or cooling a large, complex building with many zones and many diverse needs for temperature control. A technology called Variable Refrigerant Flow (VRF), popular in Europe and growing in the U.S., saves building managers money and aggravation compared to conventional HVAC systems.

Conventional HVAC systems are turned totally on for heating or cooling until not needed, then turned totally off. VRF differs in that it varies the flow rate of water or refrigerant being delivered via piping to the fan coil/air handling units of each zone from an outdoor unit, based on individual sensors / controls in each room. The basic outdoor unit is a pump that will either heat or cool the building, but will vary the flow depending on the changes needed. Some advanced systems allow heat recovery where captured wasted energy from one room can be used in another. It allows different parts of the building to be heated or cooled at the same time. Certain outdoor units can heat or cool up to 50 rooms.

VRF is most appropriate for buildings with complex heating/cooling zones or varied requirements, such as hospitals, schools, hotels, multi-family housing, retail complexes, and certain offices.

VRF typically reduces energy usage by over 30% compared to traditional HVAC equipment. It has lower installation, maintenance, and lifecycle costs than traditional HVAC equipment, it lighter in weight than chilled-water systems, reducing the load on a roof. VRF requires less duct space than conventional systems, improved the aesthetics of a building’s exterior, allowing repurposing of otherwise unusable space, removes the need for window AC units, and increasing design flexibility for contractors / installers. VRF systems are quieter, and have less opportunity for mold growth. It can be used with smart systems to deliver accurate reports on individual room / occupant energy usages, allowing more accurate charging of tenants.

One disadvantage of VRF is its initial high capital cost. However, given its energy savings, VRF should be a good long-term investment, and likely qualifies for energy incentives and low-cost financing. Another problem to note is the shortage of contractors experienced in installing and starting up such a system.

Thanks to EE Reports (www.EEReports.com) which provided information about VRF and is a source of much energy savings technology information.

CCES can help your building evaluate your energy usage and demand and recommend strategies and technologies that will save you significant cost, provide additional financial benefits, and improve building value and worker productivity. We can produce results for your buildings now. Contact us at 9140584-6720 or at karell@CCESworld.com.