C016 -- Demonstration of Combined Envelope Upgrades and Low Capacity HVAC Systems in Single-Family Homes for Improved Comfort and Energy Performance ✓ Most Recent

This project demonstrated the energy and comfort-related performance of a high-efficiency, low capacity heating, ventilation, and air conditioning (HVAC) system that replaced the existing HVAC systems in five single-family homes located in and around Los Angeles, California. The low capacity HVAC system consisted of a two-stage furnace of 26 and 40 kBtu/h capacity paired with a two-stage air conditioner of 1.5 and 2 ton capacity. The five test homes also received modest envelope upgrades like additional attic and duct insulation as well as air sealing. Utility data was collected from the test homes before and after the envelope retrofits and HVAC replacement. To support the utility data analysis, building energy modeling was performed. The utility data analysis and building energy modeling results indicated that the envelope and HVAC upgrades could reduce the HVAC energy consumption by 20 percent or more in the demonstration homes. The project tracked and analyzed comfort conditions within the homes following the envelope upgrades and switch to the low capacity HVAC system. Site monitoring of indoor conditions and responses to surveys indicated that all homeowners were more comfortable during the post-retrofit period with the low-capacity HVAC system. See more