I once heard someone say, and I have since repeated many times, that BTUs ride on the back of cubic feet of air (CFM). As I’ve learned more, I’ve come to the conclusion that the weight or mass of the air passing over the evaporator coil is far more important to understand both in terms […]

Callbacks are horrible. They kill the trade from every possible angle. They destroy customer satisfaction and reduce technician morale by causing long hours, resulting in unprofitability for companies and overall less earning opportunity for everyone. Possibly worse of all, callbacks tell customers that you are no better than their cousin the maintenance man, or worse, […]

In HVAC/R, we are in the business of moving BTUs of heat, and we move BTUs via pounds of refrigerant. The more pounds we move, the more BTUs we move. In a single-stage HVAC/R compressor, the compression chamber maintains the same volume no matter the compression ratio. The thing that changes is the number of […]

 In this episode, Bryan is joined by Matthew Taylor, a supermarket refrigeration specialist whose expertise centers on CO₂ rack systems, and Andrew Greaves, Director of User Experience at NAVAC Tools, for the third installment of their series on triple-point evacuation. The conversation expands beyond water to bring CO₂ into the picture, exploring where the […]

 In this long-awaited live episode of HVAC School, host Bryan Orr reunites with three industry veterans — Jim Bergmann of measureQuick, Roman Baugh (Kalos), and Andrew Greaves of NAVAC — to tackle one of the most pressing and underaddressed challenges in modern HVAC: performing refrigerant recovery and system evacuation in extreme cold-weather conditions. The […]

Andrew Greaves joins us again from AHR 2020. This time, he discusses what mentors and role models do in our trade and why they’re important. Mentors are not just the grouchy senior techs who throw hammers at apprentices. Mentors have an active role in others’ professional development; they spend a lot of time with their […]