Most HVAC service calls are electrical. This is the course that teaches you to find the fault with a meter and a wiring diagram, on real equipment, in six minutes or less. You learn it on our 20 diagnostic gas furnaces, each wired with real failures, and the skill carries to every system you will touch: variable-speed heat pumps, ductless systems, combi boilers and furnaces. 90% hands on, built for career changers as much as working techs, and contractors hire straight out of this class.
Live from the schedule. Day and evening sections post throughout the year.
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Understanding wiring diagrams and accurately testing systems, both electrically and mechanically, is essential for every service technician. Regardless of the season or equipment type, if it runs on electricity there is a 75% chance every service call starts the exact same way: pulling out your meter.
Skip the textbooks and headaches. The GS 102 Electrical Troubleshooting & Gas Furnace Service course puts you hands-on with real working equipment. Using your meter, you will diagnose a minimum of 100 service calls on our diagnostic furnaces, gaining real-world experience and confidence fast. Real wires, real equipment, real-world skills.
This course offers a rare, hands-on opportunity to master electrical wiring and troubleshooting. Because line and control voltage diagnostic techniques apply to all electrical equipment, learning on live gas furnaces gives you practical, real-world experience that textbooks simply cannot match.
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.
Many techs follow GS 102 with the cooling side of the trade, and the two orders work equally well. These pair naturally:
Your application is pre-filled for GS 102 when you click through. Call if you’d rather talk first. A real person picks up.