Book updated June 2026.
So you’re ready to get your state HVAC license. That’s a big deal, and honestly, you’ve already made it past the hard part—you put in the hours, learned the trade, probably froze in a few attics and sweated through more crawlspaces than you’d like to remember. Now there’s just one thing standing between you and that license: the exam.
Here’s the thing about the HVAC license exam. It’s not really trying to trick you, but it does expect you to know a whole lot of stuff. We’re talking refrigerants and combustion, electrical theory and load calculations, duct sizing, venting, code requirements, safety procedures—the list goes on. And if you’ve been out of school for a while or you learned most of what you know on the job, sitting down for a written test can feel completely different from troubleshooting a furnace on a freezing Tuesday night.
That’s exactly why this book exists. It’s not a textbook, and it’s not going to bore you with long explanations about things you already know. What it will do is give you a whole bunch of practice questions – some are straightforward, some make you think, and a few are designed to trip up the guys who didn’t study hard enough. Go through these questions, check your answers, read the explanations for the ones you missed, and by the time you’re done, you’ll walk into that testing center with a whole lot more confidence.
Don’t just blast through these questions and call it a day. The real learning happens when you get one wrong, stop, and figure out why. That’s where the magic is. So take your time, work through the chapters in whatever order makes sense to you, and if you find yourself struggling with a particular topic, go back to your textbooks or hit YouTube for a refresher. This book is your practice field, not your only playbook.
BTW, Michigan requires mechanical contractors and journeymen to pass specific state exams for different work classifications. Administered by PSI, these open-book exams are based on the Michigan Mechanical Code and require a minimum score of 70% to pass. This book covers the trade exam.
Alright, enough talking. Grab a pencil, find a quiet spot, and let’s get you ready to pass that exam. You’ve got this.
