90% hands on. Real furnaces. Real faults. A year’s worth of no-heat service calls condensed into one fast-paced course, with graduates able to diagnose a furnace in six minutes or less.
Live from the schedule. Day and evening sections post throughout the year.
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Home / Courses / Gas Furnace Troubleshooting
Curriculum, tools, schedule, and tuition breakdown. Enrollment and upcoming dates are above.
Service work in the HVAC trade is roughly 75%+ electrical problems, and it takes a disciplined procedure to diagnose those failures correctly and efficiently. The fastest way to build that skill is to put your hands and head on real systems under seasoned professionals using a structured approach.
GS 102 focuses on practical application of line and low-voltage controls on gas furnaces. By the time you finish, you should be able to correctly diagnose a furnace fault in six minutes or less.
This is a 90% hands-on course. The path runs from basic electricity, to wiring up real circuits, to troubleshooting bench boards, and finally to diagnosing live furnaces, in the same order a tech learns the trade in the field.
Once the basic electrical circuit and reading wiring diagrams are established, students get wiring boards loaded with real, functioning components. Wire by wire, students physically connect components and build circuits that actually work when wired correctly. They wire three different ignition systems against the diagrams:
Once the wiring boards are mastered, students move to troubleshooting boards wired to the same diagrams they already know. Now instead of building circuits, they trace electricity through them. Built-in fault switches fail a component electrically and produce the same readings as a real failure in the field.
Each diagnostic furnace contains 10 designed electrical failures. With every fault off, the unit operates as a normal working furnace. Students must complete a minimum of 100 simulated no-heat service calls using just their meter and the wiring diagrams. Final exam: 10 faults in 60 minutes, 100% accuracy.
Six chapters, weighted heavily toward electrical content because that is where most service calls live. Total: 110 electrical questions · 23 non-electrical · 129 total.
Day and evening sections fill on a first-come basis, so call if you want us to hold a seat.
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