David made the painful decision to lay off three of his employees. He says it was at this time that NCI’s Rob Falke counseled and helped David to stay the course – which he says was a huge factor in keeping the company’s doors open and led to them thriving.

He changed the company’s direction from new construction and began building his residential service and replacement business.

A Legacy Built Before High Performance Had a Name

It’s clear that system performance wasn’t just a business goal for the Coziahrs — it’s a family legacy. Walter Jr. was part of the University of Illinois’ early studies on residential HVAC systems, conducted long before the phrase High-Performance HVAC contracting existed.

Those studies, supported by the National Warm Air Heating and Air Conditioning Association — the organization that eventually evolved into the Air Conditioning Contractors of America (ACCA) — were groundbreaking. They sought to understand how real-world HVAC systems performed once installed in homes. In an era when “testing” often meant holding your hand over a register to see if it felt warm, this measured, data-driven approach was decades ahead of its time.

David Coziahr standing next to his working HVAC
system demonstrator holding a Testo manometer
during a high school career day event.

Dave’s father participated in that research, helping to shape the foundation of modern system performance testing. He was, in many ways, practicing high performance long before the industry had a name for it.

“Those guys were doing the real work before any of us knew what high performance meant,” Dave says with pride. “I grew up around that mindset — that you don’t guess, you prove. You don’t assume, you test.”

Education: The Heart of the Coziahr Legacy

Training has been a central value of the Coziahr family for nearly 50 years.

In the 1970s, Walter helped introduce trade education into the local school system, including what would later become the local high school’s vocational program.

Today, Dave continues that legacy. He says, “We support the TradeWorks Academy program here,” he says. “It is offered to first and second-year high school students who can explore HVAC, plumbing, welding, electrical, metal fabrication, and auto mechanics.

“Plus, The TradeWorks at IWCC (Iowa Western Community College) is offered to third and fourth-year students, with classes held on the IWCC campus.”

The Making of a Craftsman

From a young age, Dave says he was fascinated by how systems worked — not just in theory, but in the messy, unpredictable conditions of real homes. His father’s influence was both technical and philosophical: you must understand the science, respect the process, and treat every job as if it mattered, because it does.

Today, many customers consider Dave’s work to be art. His custom-built filter cabinets, for example, are hand-crafted to perform and to last. He builds them to be beautiful, functional, and modular — so they can be easily disassembled, serviced, and even reused. These aren’t factory parts or quick fixes; they’re tangible proof of a craftsman’s care.

Click Below for the Next Page:

Pages: 1 2 3 4