Explains how to test a fan motor by checking shaft movement and measuring resistance between terminals. Also covers diagnosing bad windings and freeing stuck bearings with oil if ports are available.

Learn how to test single and dual capacitors that power motors (HVAC, refrigerators, pumps), interpret microfarad (UF) readings, and identify failures like bulging. Understand that hard start kits are temporary aids and how to match UF and voltage specs when replacing.

Explains how to charge mismatched HVAC systems when superheat and subcooling aren't reliable. Covers pressure targets for R-22 and 410A, signs of proper charge, and the importance of rechecking after peak demand.

Learn how to test a scroll compressor by identifying its run, common, and start terminals and checking resistance with a multimeter.

Learn how contactors in HVAC systems use a 24-volt coil to control power flow, how they operate to supply 240 volts to compressors and fan motors, and common failure causes like obstructions or arcing. Understand how sealed contactors protect against insect damage.

Understand the purpose of a B-flow dryer filter in HVAC systems to block water and dirt from the refrigerant. Learn the importance of proper installation direction and careful brazing techniques to protect the internal moisture and debris-catching components.

Understand the role and testing of an HVAC fan relay, which uses 24 volts to activate and powers the fan motor with 240 volts (split as 120 volts per side). Learn to safely troubleshoot by checking voltage at the relay and testing the thermostat wiring to diagnose fan issues

Learn about manifold gauge sets with high and low sides that measure pressure and temperature for refrigerants like R-22 and R-410A. Understand the importance of inspecting hoses for damage, using low-loss fittings, and protecting hoses from sunlight to prevent leaks, avoid EPA fines, and ensure safe handling of refrigerants.

Learn how electric heat strips provide warmth in furnaces and heat pumps, working as emergency or primary heat sources. Understand their components—contactor, thermostat, and fuse links—and how to test each for proper function and safety.

Covers heating elements in electric furnaces and heat pumps, including contactors, thermostats, and fuse links. Learn how to troubleshoot by checking contactors, matching thermostat temperatures, testing fuse links for continuity, and ohming elements after removing wires. Also, understand the importance of pre-stretching new elements and verifying fuse link ratings.