Practical Loads, Ducts and Sales w/ Brynn Cooksey

This episode features an insightful conversation with Brynn Cooksey, an experienced HVAC contractor and trainer from Southeast Michigan. Brynnn shares his expertise on conducting proper load calculations, sizing 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.

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