Sources
Why does airflow matter?
- International Comfort Products, packaged heat pump installation instructions (350 to 450 CFM per 12,000 BTU/h; heating airflow per rating-plate rise)
https://www.shareddocs.com/hvac/docs/1011/Public/04/51801200403.pdf - HVAC School, Furnace Air Temperature Rise
https://www.hvacrschool.com/furnace-air-temperature-rise/ - Florida Solar Energy Center, Hidden Power Drains (2001)
https://fsec.ucf.edu/en/publications/html/FSEC-PF-361-01/ - Florida Solar Energy Center, Impact of Evaporator Coil Air Flow in Residential AC Systems (1997)
https://publications.energyresearch.ucf.edu//wp-content/uploads/2018/06/FSEC-PF-321-97.pdf - AC Service Tech, Measuring Airflow in CFM Using the TrueFlow Grid
https://www.acservicetech.com/post/measuring-airflow-in-cfm-using-the-trueflow-grid - The Energy Conservatory, TrueFlow Air Handler Flow Meter Operation Manual (2006), chapter 1
https://www.energyconservatory.com/wp-content/uploads/2014/07/TrueFlow-Manual-DG700.pdf - Energy Vanguard, The 2 Primary Causes of Reduced Air Flow in Ducts
https://www.energyvanguard.com/blog/the-2-primary-causes-of-reduced-air-flow-in-ducts/ - Consortium for Energy Efficiency, Duct Retrofit Decision Guide (2024)
https://cee1.org/images/pdf/CEE_Duct_Retrofit_Decision_Guide_TRC_01.16.24.pdf - NREL ResStock documentation, heat pump upgrades (existing duct airflow รท 400 CFM per ton)
https://resstock.readthedocs.io/en/2025_release_1/advanced_tutorial/heat_pump_upgrades.html - Energy Vanguard, Will a Heat Pump Work With Your Existing Ducts?
https://www.energyvanguard.com/blog/will-a-heat-pump-work-with-your-existing-ducts/ - Bonneville Power Administration, PTCS Airflow Test detailed instructions (altitude note)
https://www.bpa.gov/-/media/Aep/energy-efficiency/residential/residential-ptcs-essentials/airflow-test-detailed-instructions.pdf - Contracting Business, Find Required Heating Airflow at High Altitudes
https://www.contractingbusiness.com/residential-hvac/document/20870577/find-required-heating-airflow-at-high-altitudes