Introduction to HVAC Systems

Most people assume HVAC is about heating and cooling. It's not, exactly. It's about control: keeping the air at the right temperature, the right humidity, and with enough fresh air moving through it that people feel comfortable and breathe safely. This course starts there, with what comfort actually means and why it's harder to engineer than it looks, then builds outward into the systems designed to achieve it. You'll learn how residential systems work, from central split systems to heat pumps and ductless mini-splits, and how commercial systems scale up to serve entire buildings and campuses. Each system type gets covered on its own terms: how it works, where it's used, and how to recognize it in the field. The second half of the course is about doing the work. You'll learn the six core diagnostic tools every HVAC technician carries, including the manifold gauge set, multimeter, manometer, and combustion analyzer, and what the readings from each one actually tell you about a system's health. Safety gets its own full unit because HVAC work regularly puts technicians near live electrical panels, pressurized refrigerant lines, combustion gases, and rooftop equipment, sometimes on the same job. OSHA regulations, EPA refrigerant rules, and lockout/tagout procedures aren't abstractions here. They're the practices that keep you from getting hurt. By the end, you'll have a working mental model of the entire HVAC industry: the physics behind the systems, the systems themselves across both residential and commercial applications, the tools used to evaluate them, and the safety standards that govern the work. This is the foundation course. Everything you learn in the field, in further training, or on the job will connect back to what's covered here.