Finding the right temperature that will make most people comfortable can be a difficult balancing act. However, the installation of VRF heat pumps enable separate rooms in a central system to have independent temperature control, ending the fight over the thermostat.
While VRF, or variable refrigerant flow, is common in Europe and Asia, the technology is relatively new in the US. However, its use is growing in both residential and commercial buildings. VRF systems enable each room or zone with an indoor air handling unit to have its own temperature setting. VRF heat pumps are generally available in two types: 2-pipe or 3-pipe systems. Most 2-pipe systems require all indoor units be either in cooling or heating mode; while 3-pipe systems incorporate heat recovery capabilities that enable cooling and heating to be done simultaneously in different parts of the building.
One 2-pipe VRF heat pump that functions like a 3-pipe system is Mitsubishi’s CITY MULTI brand. This heat pump utilizes a BC Controller that includes a liquid and gas refrigerant separator, allowing heating and cooling to be done at the same time on a 2-pipe system.
VRF Heat Pumps are small enough to fit in most rooms
The outdoor unit of a VRF system is similar in size to other heat pumps and air conditioners. The indoor component of a VRF heat pump generally takes the form of a cassette, floor mounted, or wall mounted unit, and is attached to the outdoor unit through refrigerant piping. VRF units do not use ductwork, which frees up square footage inside the building and makes them to cheaper to install in buildings that do not have ductwork.
Energy efficiencies in all the right places, but only at the right temperatures
Because VRF heat pumps can control the temperature of individual zones, units can be turned off in zones that are not occupied, increasing energy efficiency. Heat recovery systems can provide even greater energy efficiency as the waste heat from a zone in cooling mode can be transferred to provide heat to a unit in heating mode, without the need to cycle the refrigerant back to the outdoor unit.
Similar to most other air source heat pumps, efficiency gains decrease as the temperature goes down. As a result, VRF heat pumps are not ideal in areas where cold temperatures dominate for much of the year. The tipping point is generally around freezing. At or below this temperature, heat pumps cannot provide enough heat into a building to counter the heat lost through the walls and windows. However, a number of models are rated for use at below freezing temperatures.
Research on the Heat Pump Market
For more information, see the Heat Pump Market in the US industry study by The Freedonia Group. This comprehensive report provides vital information on market environment factors and analysis on the following:
- Supply & demand
- Product outlook
- Industry composition
- Market share
- Mergers & acquisitions
- And much more
About the Author:
Kyle Peters is the Assistant Manager of the Machinery and Equipment Group at The Freedonia Group, where he works on studies related to the US and global machinery, appliances, and industrial components markets.