This episode features an insightful conversation with Brynn Cooksey, an experienced HVAC contractor and trainer from Southeast Michigan. Brynn shares his expertise in conducting proper load calculations, sizing the equipment correctly, improving duct design, and addressing common issues contractors face. Brynn emphasizes the importance of performing accurate load calculations, especially in older housing stock where equipment is frequently oversized by 50% or more. He discusses how oversized equipment leads to short cycling, poor efficiency, and increased utility costs for homeowners. His approach involves educating customers by involving them in the measurement process and using metrics like "duct deficiency" to demonstrate the inefficiencies of their current systems. The discussion then shifts to heat pumps and the unique challenges of implementing them in cold climates like Michigan. Brynn advocates for a "dual fuel" approach, utilizing heat pumps for efficiency while supplementing with gas heat during extremely cold temperatures. He stresses the necessity of a tight, well-insulated thermal envelope and proper duct design to ensure optimal heat pump performance. Topics covered include: Conducting blower door tests for accurate load calculations Downsizing equipment and solving duct issues in retrofit applications The "duct deficiency" metric for demonstrating system inefficiencies Aeroseal duct sealing: benefits, limitations, and proper application Identifying and addressing cracked heat exchangers due to airflow issues Training sales teams on a hands-on, educational sales process The importance of building science education for contractors Overcoming hesitancy in trusting load calculation results Brynn encourages contractors to embrace building science principles, trust the load calculation process, and focus on system design rather than simply swapping out equipment. By proving these methods to themselves, contractors can transform their businesses and deliver true value to customers through improved comfort, efficiency, and cost savings.   Learn more about HVAC U and its course offerings at https://www.hvactrain.com/.  Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.  Purchase your virtual tickets for the 5th Annual HVACR Training Symposium at https://hvacrschool.com/Symposium24.  Subscribe to our podcast on your iPhone or Android.   Subscribe to our YouTube channel.  Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.