Heat Recovery VRF Systems

Heat Pump Technology

Heat pump systems offer an energy-efficient alternative to furnaces and air conditioners for all climate zones and it's not a new technology. In 1948, American inventor Robert C. Webber noticed excessive heat rejection from his deep freezer and devised a way to capture this heat to boil water, which when run through a coil with a fan blowing over it could produce comforting heat. This discovery eventually led to the use of a pressure-actuated reversing valve on the refrigerant system, which allows an HVAC unit to invert the refrigeration cycle to provide either cooling or heating as a heat pump.

Like your refrigerator or Webber's deep freezer, heat pumps use electricity to transfer heat from a cool space to a warm space, making the cool space cooler and the warm space warmer. When cooling, heat pumps operate at the same level of efficiency as traditional air conditioners.

When heating, heat pumps outperform standard baseboard heaters and furnaces several times over. Rather than producing heat through combustion of fuel, heat pumps produce heat by moving or displacing it. According to the U.S. Department of Energy, today's heat pumps can reduce electricity use for heating by approximately 50% compared to electric resistance heating. A heat pump's ratio of heat energy output to energy input, or the Coefficient of Performance (COP), is greater than 100% and frequently between 300% to 400%! For example, a heat pump with a COP rating of 3.2 produces heat energy by a factor 3.2 times greater than the energy input that powers the unit.

Heat pumps also dehumidify better than standard central air conditioners, resulting in less energy usage and more cooling comfort in the warmer summer months. Other advantages of heat pump systems include:

• Lower operating costs
• The ability for a single unit to provide both heating and cooling
• No fuel exhaust and no need to install a ventilation system
• Variety of product designs and sizes that allow for zonal or central air conditioning in commercial applications
• Lower carbon emissions due to the high conversion rate of energy to heat
• PSO incentives to help pay for high efficiency heat pump systems

Variable Refrigerant Flow Technology

Variable refrigerant flow (VRF) or variable refrigerant volume (VRV) applies all the benefits of heat pump technology to large areas or entire buildings. This technology was invented and trademarked in 1982 by Daikin and originally released in Japan. VRF made its way to the United States in 2004, and its revolutionary approach to on-demand heating and cooling has seen excellent growth in adoption and application.

Heat pump VRF systems have lower overall energy consumption than traditional HVAC system designs. Their modular cassettes allow for easy installation and service with the ability to stage condensing units for even deeper energy savings. VRF is a great option for new construction projects, existing building renovations and HVAC system retrofits.

Multiple cassettes in a VRF system can provide either heating or cooling from one condensing unit. In the example below, half of the building is cooled, and the other half of the building is heated simultaneously by two condensers.

Heat Recovery VRF Technology

Heat recovery VRF systems go one step further by allowing each cassette to heat or cool independently, providing heating to some areas while providing cooling to other areas from the same condenser.

These systems offer simultaneous heating and cooling by transferring exhaust heat (or waste heat) from a zone that's calling for cooling to a zone that's calling for heating.

As an example of a commercial application, a typical office consists of open plan workspaces and various meeting rooms of differing sizes, all of which require different temperature needs depending on not only their occupancy but also the orientation of the rooms. If an office space is being cooled, the excess energy being removed is transferred into an area that requires heating. Offices that have east and west facing rooms can balance out the distribution of heating and cooling needs with heat recovery VRF, which will transfer the excess energy from one side to the other.

Applying this technology to a whole floor or even an entire building increases air conditioning efficiency greatly and can lower energy usage by up to 30% and in some cases, even more. Heat recovery VRF systems promote higher energy efficient ratings and can contribute to a green building certification.

If you're interested in installing a heat pump, VRF or heat recovery VRF system, please reach out to your local PSO's account representative to learn more about available PSO rebates to help pay for the energy efficient equipment!