EP239 Psychrometrics, Mobile Apps, and the Future of HVAC with Carmel Software (September 2025)

EP239 Psychrometrics, Mobile Apps, and the Future of HVAC with Carmel Software (September 2025)

Author: Bill Spohn October 10, 2025 Duration: 32:06

Stephen Roth—founder of Carmel Software and current owner of Hands Down Software—joins Bill and Eric to trace a multigenerational journey from a 1920s Ohio roofing firm to modern HVAC software that powers everyday field work. Stephen shares how family roots in commercial roofing and energy management shaped his path as a mechanical engineer and coder, eventually leading to Autodesk acquiring his early load-calc assets and, later, to relaunching Carmel with one of the industry's first mobile HVAC app suites.

Today CarmelSoft offers field-friendly tools from PT charts and duct/pipe sizers to an ACCA-approved Manual J (HVAC ResLoad J) iPad app. Stephen also discusses custom projects for Carrier, Mitsubishi, SMACNA, and ASHRAE (including Building EQ), plus the acquisition and revitalization of the ubiquitous Hands Down psychrometric chart software. Looking ahead, he sees AI accelerating data entry, plotting psychrometric processes by prompt, and facilitating web-based collaboration—always in service of the core mission: helping technicians and engineers accurately size systems and design energy-efficient buildings.

Notable quotes:

"Our mission is to help technicians and engineers easily and accurately design energy-efficient buildings." — Stephen Roth

"The city of Phoenix wouldn't exist without our industry." — Stephen Roth

 

 

Stephen's LinkedIn: https://www.linkedin.com/in/stephenbroth/

Camelsoft website: https://carmelsoft.com/

HandsDown website: https://www.handsdownsoftware.com/

Upcoming webinars: https://carmelsoft.com/Carmel-Software-Mobile-Training-Webinars

Past recorded webinars: https://carmelsoft.com/Carmel-Software-Video-List

Contact form: https://carmelsoft.com/Carmel_Software_ContactUs.aspx

 

This episode was recorded in September 2025.

 


Ever wonder why some buildings feel just right-healthy, comfortable, and surprisingly efficient-while others seem to work against you? That’s the territory explored in Building HVAC Science, a podcast hosted by seasoned experts Eric Kaiser and Bill Spohn. This isn't just about thermostats and ductwork; it's a deep, practical dive into the physics and principles that make indoor environments work. You’ll hear conversations that dissect real-world diagnostics, question common practices, and explain the often-overlooked science behind temperature, airflow, and moisture. The discussions naturally progress from foundational concepts to the latest tools and technologies used for measurement and verification, always linking theory to tangible results in building performance. By focusing on the interplay between proper HVAC design, installation, and human well-being, this podcast provides actionable knowledge for professionals and curious minds alike. Tune in for a clear-eyed look at how understanding the built environment leads to spaces that are better for both people and the planet.
Author: Language: English Episodes: 100

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