In this episode of the HVAC School Podcast, host Bryan sits down with Johnny, the creator behind the popular social media channel "Let's Be Techs." Johnny brings a wealth of hands-on experience to the table, having spent his first 13 years in residential HVAC before transitioning into commercial refrigeration. He shares his unconventional path into the trade—starting out building houses before being recommended to an HVAC contractor—and how the lack of quality mentorship early in his career motivated him to create educational content for technicians. His videos, which began as a fun hobby and a way to teach his helper remotely, have since grown exponentially across TikTok, YouTube, and Facebook, and continue to attract technicians hungry for practical, real-world knowledge.

The bulk of the episode is a deep dive into real-world troubleshooting strategies, covering everything from the very first moments you arrive on a job site to diagnosing complex intermittent electrical faults. Bryan and Johnny both emphasize the value of using your senses before reaching for specialty tools—listening for surging liquid lines, feeling condenser airflow with your hand, and visually inspecting service valves for oil before removing caps. They share a mutual philosophy that the best technicians are those who can step back, assess the big picture, and narrow down the problem systematically rather than immediately jumping to assumptions about charge levels or component failures.

A significant portion of the conversation centers on low-voltage electrical diagnostics, an area where both techs have noticed major changes over the last several years. Bryan and Johnny discuss the rise of contactor coil failures, transformer overload from aftermarket add-ons like UV lights and zone dampers, and the clever use of a contactor in place of a fuse as a low-cost short-finder tool. They also revisit the concept of "tattletale" fuses and resettable fuses, comparing their reliability and appropriate applications. Throughout these discussions, both hosts bring in personal war stories that make the technical content feel grounded and immediately applicable to everyday service calls.

The episode wraps up with discussions on thermal imaging cameras, scroll compressor anomalies, and a memorable consulting story from Barbados involving a VRF system. Johnny and Bryan also touch on the importance of sharing knowledge openly in the trades, pushing back against the gatekeeping mentality that leaves newer technicians struggling to find reliable information. Both agree that the comment sections of field-focused videos have become a valuable community resource—a place where techs teach each other, correct each other, and build a collective knowledge base that benefits the whole industry.

Topics Covered

Johnny's background: from construction to HVAC apprenticeship to commercial refrigeration
How "Let's Be Techs" started as a fun hobby and grew into a major social media presence
Using your senses first: listening, looking, and feeling before pulling out specialty tools
Checking service valves for oil and inspecting caps/seals before connecting gauges
Walk-in cooler first-response checklist: fans, thermostat display, suction line frost, liquid line surging
Feeling condenser airflow direction to diagnose dirty or clogged coils
Identifying capacitor and contactor issues from the moment you approach residential equipment
The rise of contactor coil failures and how location-based dirty power contributes
Transformer overload: understanding the 40 VA / 24V current rating and why a 5-amp fuse doesn't protect windings
Aftermarket add-ons (UV lights, dampers, zone systems) overloading low-voltage circuits
Float switches fusing closed from excess current draw
The contactor-as-short-finder trick: a DIY alternative to the Short Pro tool
Adding individual circuit fuses ("tattletale" fuses) for isolating intermittent low-voltage shorts
Resettable (popper) fuses: reliability issues and why 3-amp versions outperform 5-amp versions
Contextual diagnostics: thinking about when and why a fuse blew (weather, season, recent activity)
The 225°F discharge line rule for monitoring compressor health
Scroll compressor oddities: running backwards, check valve failures, and starting under equalized pressure
VRF system quirk: electronic expansion valves staying open when power is cut to one air handler
Thermal imaging cameras: practical applications in the field including electrical panels, motors, condenser coils, and compressor racks
Using black tape (gaffer's tape) to improve thermal imaging accuracy on shiny surfaces
Megohmmeter use for finding wire shorts that are intermittent but close to failing
The importance of anti-gatekeeping: sharing knowledge freely and learning from community feedback

Follow Johnny on social media as "Let's Be Techs" on YouTube, TikTok, Facebook, and Instagram.

Have a question that you want us to answer on the podcast? Submit your questions at https://www.speakpipe.com/hvacschool.

Purchase your tickets or learn more about the 7th Annual HVACR Training Symposium at https://hvacrschool.com/symposium.

Subscribe to our podcast on your iPhone or Android.

Subscribe to our YouTube channel.

Check out our handy calculators here or on the HVAC School Mobile App for Apple and Android.