Less Guesswork. Better Diagnostics. Fewer Callbacks.
Real-world HVAC training for technicians, contractors, distributors, and OEM teams.
Trusted By Industry Experts
About Don Gillis
With over 33 years in the HVAC industry, I’ve worked every role — from tech to field supervisor to national manager for elite manufacturers and organizations. I know the headaches of inefficient, confusing systems, and what exactly teams are up against in the field and on tricky applications.
I’ve built my training to give techs & contractors practical ways to understand, help people make better decisions, and get the job done right the first time.
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.
The Problem &
.The Solution
The Problem
High Technician Turnover
Frustration from knowledge gaps leads to burnout and technicians leaving the industry at record rates.
Rapidly Evolving Technologies
The industry is shifting faster than standard education can keep up with (A2L, CO2, Inverter tech).
Knowledge-Experience Gap
A widening divide between basic field experience and the deep technical mastery required for modern systems.
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.
Technical Confidence & Retention
Empowered technicians are more productive, make fewer errors, and remain loyal to the companies that invest in them.
Core Trainings
Specialized Technical Trainings
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, static pressure measurement, and airflow analysis. Learn to recognize system patterns before you ever
Inside the Machine
"Every Component. Every Function. No Guessing."
Compressors, metering devices, coils, filter driers, electric motors, and scroll anatomy — know what every part does, why it fails, and what to look for.
When Things Go Wrong
"Diagnose It Fast. Fix 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. Are You Ready?"
CO₂ (R-744), Propane (R-290), A2Ls — get ahead of the refrigerant transition before it gets ahead of you.
Built for You
"Every Course, Customized to Your Team"
From distributor soft skills to technician Level 1 & 2 training shaped around your people, your market, and your goals.
Training & Development Focus
Contractors
Customized field training designed to reduce call-backs, improve technician retention, and increase overall service profitability.
OEM's
Partnering with manufacturers to deliver specialized training that ensures proper field installation and reduces warranty claims.
Distributors
Upskilling counter and sales teams to provide expert technical support, helping customers find the right solutions faster.
Train The Trainer
Empowering your internal leaders with the tools and teaching techniques to deliver high-impact technical training themselves
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.
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.
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