Speaker: Thomas Hartman, P.E.
Thomas Hartman is Principal and the founder of The Hartman Company, a technology development and applications firm that works with designers, manufacturers and end users to apply emerging ultra-efficient HVAC and lighting technologies. Among the most notable of Mr. Hartman’s developments have been the “Equal Marginal Performance Principle” and relational control concepts. These provide new approaches to integrating variable speed and other new HVAC/Lighting technologies with network controls for simpler, lower cost and better performing building comfort systems.
Tom Hartman holds a number of patents for advanced technologies and works world wide with manufacturing and engineering partners to develop sound, cost effective products and designs that utilize these technologies for a wide variety of applications. In addition to the development of the Equal Marginal Performance Principle and relational control, Hartman has developed and works to apply a number of other indoor comfort enhancing technologies. Tom currently serves as an editorial advisor to Heating, Piping and Air Conditioning Magazine and the on-line publication, automatedbuildings.com. Tom is also a member of ASHRAE SSPC 55 and lectures and writes about comfort and energy issues for major symposiums and periodicals all over the world.
Program: Relational Control: HVAC System Control for the 21st Century
Combining variable speed and digital network technologies provide new and exciting energy efficiency enhancing opportunities with what are called “relational control” techniques. Relational control employs the network capacity of modern DDC systems to operate each HVAC component in accordance with system requirements and in an
optimal relationship to the current operation of all other system components. Relational control techniques offer dramatic improvements in energy efficiency, stability and system performance. This new family of control strategies represents a significant change from the stand alone nature of PID control that is still widely employed today. But this newer technology requires new industry process and practices to achieve success in implementation. So when relational control techniques are applied to achieve ultra-efficient system performance, the process through which it is applied needs to be changed as well to be certain the technologies are adequately supported and end up operating as expected.
There are currently two primary categories of relational control as applied to HVAC systems. Demand based control, which is derived from the Equal Marginal Performance Principle, is employed to optimize the operation of systems that are composed of multiple power consuming components such as central systems. Intelligent iterative control is employed to improve the efficiency and performance of systems that distribute a resource such as heating, cooling or airflow to multiple zones.
This discussion will provide an introduction to these new relational control technologies and outline their advantages over current control practice. It will also discuss the application of these technologies to actual building systems and outline the types of changes in the design / construction / startup processes that are necessary to ensure applications of these newer technologies achieve the projected results.
