Less Guesswork. Better Diagnostics. Fewer Callbacks.
Training that works when the boots hit the ground
Trusted By Industry Experts
About Don Gillis
With over 33 years in the HVACR industry, I’ve spent 25 of those years in the field as a licensed journeyman, working on the same systems and challenges technicians face every day.
My background includes roles as a service technician, service manager, territory sales manager, national trainer, and industry educator. I’ve had the opportunity to train thousands of technicians, distributors, OEMs, and HVAC professionals across the country.
My goal is simple: deliver practical, real-world training that helps people understand the system, make better decisions, and get the job done right
What's Behind my mission
Gillis Coach HVAC Consulting & Training “Driven by passion and honesty, Gillis Coach delivers high-level training that empowers HVAC professionals to grow and carry the industry forward.”
Target Audience
Who This Is For
Bridging the gap for professionals across every level of the HVACR ecosystem.
HVAC Technicans
Customized field training designed to reduce call-backs, improve technician retention, and increase overall service profitability.
Train the Trainer
Empowering your internal leaders with the tools and teaching techniques to deliver high-impact technical training themselves.
Counter People
The counter is where the job either goes smoothly or goes sideways. We train your counter staff to know the parts beyond just the SKU.
OEM Partners
Partnering with manufacturers to deliver specialized training that ensures proper field installation and reduces warranty claims.
Tech Support Mastery
Textbooks don’t sweat on a rooftop. This training is built by someone who’s been in the field, for people who work in the field.
The Problem &
.The Solution
The Problem
Lack of Employees
Workforce shortages due to retirements, promotions, and ongoing turnover are making it difficult to maintain experienced staff across all roles.
Refrigerant Mechanical Technology
Rapid changes in refrigerants, mechanical systems, and plug-and-play technologies are advancing faster than traditional training can keep up.
Knowledge–Experience Gap
As experienced professionals (baby boomers) retire, critical knowledge is being lost. At the same time, technology is becoming more complex, and a lack of effective training is making it difficult for newer workers to keep up.
The Solution
Expert-Led, Practical Training
Hands-on, real-world curriculum designed from 33+ years of actual field experience, not just textbooks.
Specialized Knowledge Transfer
Direct mastery of complex systems ensuring your team is prepared for the next generation of HVACR.
Workforce Confidence & Retention
Empowering your employees to be more productive, make fewer errors, and remain loyal to the companies that invest in them
Specialized Technical Training
Core Training
Start Here
"How Refrigeration Actually Works" The physics behind every system you'll ever touch — heat transfer, refrigerant cycles, superheat & subcooling, phase change, and P-T charts. Build the foundation that separates great techs from parts changers.
Know Your Tools
"Read the System Before You Touch It" Master the instruments that tell the truth — multimeters, manifold gauges, pressure measurement, and airflow analysis. Learn to recognize system patterns before pulling a tool.
Inside the Machine
"Learn all Components. No Guessing." Learn what each component does, why it fails, and what to look for — simplified and practical.
When Things Go Wrong
"Diagnose It Right the First Time." Real-world troubleshooting across systems, compressors, air conditioners, heat pumps, electric motors, defrost boards, and TXVs. Stop throwing parts at problems.
Next-Gen Technology
"The Industry Is Changing."
Stay ahead with evolving refrigerants, plug-and-play systems, tools, and modern equipment.
Built for You
"Every Course Customized to Team"
From soft skills to technician Level 1 & 2 training — built around your people, your market, and your goals.
Testimonials
I met Don nearly five years ago at the HVAC School Training Symposium. Since then, I have relied on him several times for technical advice. His expertise and willingness to share have helped me refine the curriculum at NCI. Don has earned his reputation through years of fieldwork and his dedication to industry education. He communicates complex topics in a way that is relatable to his audience. I consider Don both a friend and mentor. He is one of the most effective and well- spoken presenters I’ve had the opportunity to work with. Whenever I have a question, I know Don will answer the phone when needed.
What makes Don Gillis’ instruction valuable is his sincere and candid presentation. Don has personally experienced his subject matter from the ground up and that’s what adds relevance. Don Gillis is a gifted educator and story-teller. His clients benefit because his content is effective and applicable
Don has been an invaluable asset to the University of Northwestern Ohio and a trusted colleague for many years. As a longstanding member of our HVAC/R Advisory Board, he has consistently provided valuable industry updates, training, and expertise that have greatly benefited the university, our students, and fellow board members. Don has always been willing to assist in locating important information, offer thoughtful guidance, and provide knowledgeable advice whenever needed.
I’ve known Don for over six years in the HVAC industry, and he consistently goes above and beyond to help others succeed. He’s trained thousands across our organization on major industry changes and has helped create content that’s reached hundreds of thousands. Don is extremely knowledgeable, honest, and someone I trust without hesitation.
I’ve had the pleasure of attending multiple classes led by Don Gillis, and each experience has reinforced just how exceptional he is as both an educator and an industry professional. His ability to break down complex technical concepts into clear, practical insights makes his sessions incredibly valuable for both new and experienced professionals.
Frequently Asked Questions
I specialize in technical training for technicians, sales development, and specialized OEM programs.
Yes, all training programs can be tailored to meet the specific technical and business needs of your organization.
I offer both on-site hands-on training and interactive virtual sessions to ensure flexible learning options.
You can use the "Contact Now" button below or reach out via the contact information in the footer.
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