Air Source Heat Pump White Paper

  • April 13, 2021

In January of 2021 RTF staff made available a white paper summarizing the energy impacts of installation practices on single-speed air-source heat pumps installed in residences in the Pacific Northwest Region. The goal of the paper was to provide a technical explanation of the impact of installation practice to help identify promising directions for program evolution. It was written with energy efficiency program operators in mind with the energy impacts presented as recommendations for consideration in program designs. 
For over four decades, energy efficiency programs have encouraged converting electric resistance furnaces to air-source heat pumps.  The more successful programs tend to achieve higher energy savings by encouraging installers to focus on certain key installation practices or characteristics.  This paper discusses each of the installation practices and summarizes its impact on energy consumption and energy savings, along with some insight into the challenges programs may face in achieving proper installations.
At a high level, the paper highlights compressor lockout, resistance heat control and wood heat as areas with potentially major negative impacts to savings and makes program centered recommendations based on those impacts. However, the paper, linked below, looks at a much wider range of key installation practices and attempts to speak to the potential impact of all of them. 
This paper has been reviewed by the RTF's Air Source Heat Pump subcommittee and was received positively with no major disagreements. However input didn't give any specific direction for a specification to pursue for direct use in regional programs at this time. Please direct any questions or feedback regarding the white paper to Adam Hadley ( or Annika Roberts (  

Single-Speed ASHPs: Energy Impacts of Efficiency Program Design Elements