Low Voltage Diagnosis Basics w/ Bill Johnson

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Low Voltage Diagnosis Basics w/ Bill Johnson

April 3, 2018

Bill Johnson shares his practical tips to make low voltage electrical diagnosis easier

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Real training for HVAC ( Heating, Ventilation, Air Conditioning and Refrigeration) Technicians. Including recorded tech training, interviews, diagnostics and general conversations about the trade.

In this heartfelt and wide-ranging episode, host Bryan reconnects with Jim Bergmann of measureQuick after nearly three years apart. The reunion is anything but ordinary — Jim opens up about a serious battle with non-Hodgkin’s B-cell lymphoma that sent him through not one but two rounds of chemotherapy, ultimately requiring a cutting-edge CAR-T cell immunotherapy treatment at the Cleveland Clinic. Jim shares the remarkable medical journey of having his T cells extracted, genetically modified in a Maryland lab, and reintroduced into his body to permanently attack cancer cells. Now past the critical six-month remission milestone, Jim is back, healthy, and more motivated than ever to push the HVAC diagnostics industry forward.

From his medical comeback, the conversation transitions naturally into what Jim loves most: the world of HVAC diagnostics and the evolution of measureQuick. After years of defending a per-use pricing model that the market simply didn’t embrace, Jim candidly admits the old model wasn’t working. With the help of business partner Eric Preston (formerly of TruTech Tools), the team overhauled the software’s pricing structure in February — a move that has since driven 90%+ customer retention and accelerated growth significantly. The new focus is squarely on “time to value,” streamlining workflows so technicians reach key diagnostic reports faster than ever before.

A significant portion of the episode dives into how measureQuick is thoughtfully integrating artificial intelligence. Rather than chasing AI trends, Jim and his team — including AI specialist Ben Reed — took a deliberate approach: identifying the precise areas where AI genuinely helps technicians without creating distractions. The standout use case is label identification, where AI reads equipment labels and auto-populates system profiles. Jim is refreshingly candid about AI’s limitations in HVAC diagnostics, explaining that the field variability of real-world systems (varying line set lengths, mismatched equipment, non-standard airflow conditions) makes purely AI-driven diagnostics unreliable. Instead, measureQuick leans on first-principle modeling and non-dimensional mathematics to generate objective, data-driven results.

The episode closes with a thought-provoking discussion about the state of the HVAC industry at large. Bryan and Jim tackle the growing influence of private equity consolidation, the persistent problem of technicians skipping probe deployment, the difference between clearing faults and actually fixing them, and the importance of commissioning and retro-commissioning equipment to manufacturer design intent. Throughout it all, the conversation is anchored by a shared belief: that measuring everything — in business and on the job — is the foundation of genuine, lasting improvement. It’s a must-listen for any HVAC professional or business owner who wants to understand where the industry is headed.

Topics Covered

Jim’s cancer diagnosis: non-Hodgkin’s B-cell lymphoma and the progression from standard chemo to aggressive relapse
CAR-T cell immunotherapy explained: how T cells are extracted, genetically modified, and reintroduced to fight cancer permanently
Jim’s recovery at the Cleveland Clinic and surpassing the critical six-month remission milestone
Neurotoxicity as a side effect of CAR-T therapy and what that experience was like
The pivot away from measureQuick’s per-use pricing model and the dramatic improvement in retention after switching
The “time to value” philosophy driving measureQuick’s new hybrid workflow interface
How measureQuick is integrating AI — and where AI falls short in real-world HVAC diagnostics
Label identification as the most practical current AI application in field diagnostics
Why AI is highly sycophantic and the danger of relying on subjective, internet-sourced training data for HVAC decisions
The power of measureQuick’s proprietary measurement data and target zones as a foundation for AI summaries
First-principle modeling and non-dimensional mathematics: why brand-agnostic diagnostics work
The importance of deploying all nine probes on every air conditioning service call
Benchmarking vs. commissioning vs. retro-commissioning: the three layers of equipment assessment
Design temperature difference: measuring evaporator and condenser delta-T as engineering benchmarks
How ECM motors mask airflow problems — and why that leads to premature motor failure and higher energy costs
The two “elephants in the room”: incomplete probe deployment and clearing faults without fixing them
Why clearing a fault in measureQuick without addressing the root cause is like putting duct tape over a check engine light
How poor installation practices in high-growth markets (Florida, Texas, Arizona, Las Vegas) have created widespread system deficiencies
The role of private equity in HVAC consolidation and why many PE firms add cost without adding value
Why implementing field measurement systems like measureQuick is the missing link for PE-owned and independent shops alike
The legacy mode vs. new mode toggle in the upcoming measureQuick update — no forced UI changes for existing users
How measureQuick helps newer technicians become productive faster and helps seasoned technicians be more consistent
The importance of presenting diagnostic findings to homeowners and helping them understand what the numbers actually mean