The One Who Wanted the Data

"What's the leak rate? Linear decline or does it accelerate?" Structural engineer. Five minutes into the call he's already asked three follow-up questions better than most customers ask all day. The system had a refrigerant loss and a blower motor bearing starting to go. Standard enough. But this customer isn't trying to make a decision, the decisions are essentially made before he asks. He wants the mechanism. Cycle hours vs calendar time. Failure distributions. When Dave says he can't give an exact leak rate without more testing, the customer builds the model in real time: "So the rate is a function of cycle hours, not calendar time." "So refrigerant and the efficiency of the envelope are coupled." When Dave admits he doesn't have actuarial data on compressor failure, the customer says: "That's good enough. Consistent with what I'd expect from a Weibull distribution for wear-out failure." Dave had to look up Weibull when he got home. What you'll hear: - Need for cognition (Cacioppo & Petty, 1982), the stable individual difference in who enjoys effortful analytical thinking - Why depth of understanding grounds a decision instead of slowing it (one probability estimate on the blower motor, one clean decision) - Why most calls require adjusting technical depth down, and why this one required adjusting up Core quote: "Most of the time I adjust for customers who want less technical depth than I'd naturally provide. This time I had to adjust upward." Hosted by Dave Hartzell, Master HVAC technician, 45 years in the field, 90,000 service calls. NATE certified, IGSHPA accredited, Mitsubishi Diamond Dealer, Trane Comfort Specialist, BBB A+ for over a decade. Owner of Hartzell's Heat & Air in Kingfisher, Oklahoma. Proudly based in Kingfisher and serving Edmond, Guthrie, Yukon, Mustang, Piedmont, Logan County, Canadian County, Blaine County, Major County, Garfield County, and the greater Oklahoma City metro area. Facebook: facebook.com/hartzellsheatair X (Twitter): x.com/HartzellsHVAC YouTube: youtube.com/@hartzellsheatair6003 LinkedIn: linkedin.com/in/dave-hartzell-7a687515 Email: [email protected] Phone: 405-375-4822 Web: hartzellsheatair.com Keywords: need for cognition, Cacioppo Petty, analytical cognitive style, structural engineer HVAC, Weibull distribution, refrigerant leak rate, blower motor failure, compressor life expectancy, HVAC load calculations, Central Oklahoma HVAC, Master HVAC technician, Kingfisher Oklahoma, Hartzell Heat and Air