Advanced Controls for Residential HVAC Fan

Ben Schoenbauer

Past field research in Minnesota has shown that many HVAC systems do not reach the same level of efficiency in the field that they reach under laboratory and rating conditions. One opportunity to boost real-world performance and recapture some of the lost efficiency in residential systems occurs during the post-purge cycle. Some heating or cooling energy remains in the heat exchanger at the end of each burner or compressor cycle. Innovative controllers have been introduced that modify fan operation to distribute more of this energy to the house, increasing system efficiency while maintaining comfort.

This project will research the energy savings potential of a fan control device designed to reclaim HVAC losses by extending post-purge times, as well as research the market for such a product. Researchers will assess residential HVAC market and installation feasibility as well as develop a selection and diagnostic tool. Finally, analysis of monitored data from installed systems will be used to determine the energy savings, carbon reductions, and cost-effectiveness.  

This project is supported by a grant from the Minnesota Department of Commerce, Division of Energy Resources through the Conservation Applied Research and Development (CARD) program, which is funded by Minnesota ratepayers.  

Project Info


Conservation Applied Research and Development (CARD) grant program


This field study will measure the savings potential and characterize the market for a commercially available fan controller to increase the efficiency of residential heating and cooling systems. 


  • Establish project methodology
  • Market characterization
  • Field assessment
  • Model development
  • Field monitoring and evaluation
  • Assessment and analysis
  • Dissemination of findings  

Non-energy benefits

  • Reduced greenhouse gas emissions

  • Utility bill savings  

Ben Schoenbauer