"Listen first, talk last."

"Integrity costs something, you've got to be willing to pay it."

"If I'm going to fail, I'm going to go down fighting."

In this episode of the Building HVAC Science Podcast, Bill and Eric sit down with Don Gillis, a longtime industry pro with a career spanning roles as an installer and service tech, service manager, outside sales, corporate training, and now building technical training within a smaller nonprofit environment. Don shares the real story behind the resume: high-volume service management, the stress and health toll of living in "two phones to your ears" mode, and the hard decision to finally step away, even when loyalty and integrity made it feel impossible.

A big theme is the power of soft skills, especially listening. Don talks about how learning to listen changed everything: calmer customers, stronger trust, better long-term relationships, and even better outcomes inside a distributor sales role where he turned around a struggling territory by showing up as himself. He digs into what "genuine" actually looks like in the field, why people can smell a script or hidden agenda, and how trust can become so strong that customers insist on "their" technician.

The second major theme is growth through discomfort. Don repeatedly stepped into roles where he felt over his head, then compensated by obsessively preparing: reading, practicing, recording himself, and learning from people with deeper experience. The episode closes with a simple message that ties it all together: integrity and passion cost something, but they are also the multipliers that make careers durable and meaningful.

Don's LinkedIn: https://www.linkedin.com/in/dongilliscom/ Don's company: https://hardinet.org/

This episode was recorded in February 2026