Uploaded March 2026 | Updated September 2026, 2 weeks ago
What happens when you try to pull a vacuum in freezing temperatures? The answer might surprise you — and it could be costing your customers their equipment. Bryan Orr sits down with three of the sharpest minds in the trade to dig into one of the most underrated challenges facing technicians today: refrigerant recovery and system evacuation in cold weather environments.
As cold climate heat pumps become the primary heating source across North America, HVAC technicians are being called to make compressor-side repairs in sub-zero conditions more than ever before. But low ambient conditions change the physics entirely — and your micron gauge might be lying to you.
Jim Bergmann, Roman Baugh, and Andrew Greaves join host Bryan Orr for a live conversation that goes deep on the science: vapor pressure, sublimation, the triple point of water, mass transfer limitations, moisture trapped in oil, and why 500 microns is not a one-size-fits-all pass/fail number. The crew debates whether a proper vacuum is even achievable at low temps, what role desiccant dryers play on VRF systems vs. mini splits, and how heat — applied strategically — may be your only real path forward.
Andrew introduces the concept of the "heat provocation test," Jim drops hard truths from 35 years in the field, and Roman bridges the gap between theory and what's actually doable on a job site. Plus: nitrogen purging, filter driers on mini splits, scheduling changeouts before the cold hits, and why best practices must evolve when your ambient environment does.
This is the kind of conversation that changes how you work. The HVAC School livestreams is back — and we're just getting started on this topic.
What happens when you try to pull a vacuum in freezing temperatures? The answer might surprise you — and it could be costing your customers their equipment. Bryan Orr sits down with three of the sharpest minds in the trade to dig into one of the most underrated challenges facing technicians today: refrigerant recovery and system evacuation in cold weather environments.
As cold climate heat pumps become the primary heating source across North America, HVAC technicians are being called to make compressor-side repairs in sub-zero conditions more than ever before. But low ambient conditions change the physics entirely — and your micron gauge might be lying to you.
Jim Bergmann, Roman Baugh, and Andrew Greaves join host Bryan Orr for a live conversation that goes deep on the science: vapor pressure, sublimation, the triple point of water, mass transfer limitations, moisture trapped in oil, and why 500 microns is not a one-size-fits-all pass/fail number. The crew debates whether a proper vacuum is even achievable at low temps, what role desiccant dryers play on VRF systems vs. mini splits, and how heat — applied strategically — may be your only real path forward.
Andrew introduces the concept of the "heat provocation test," Jim drops hard truths from 35 years in the field, and Roman bridges the gap between theory and what's actually doable on a job site. Plus: nitrogen purging, filter driers on mini splits, scheduling changeouts before the cold hits, and why best practices must evolve when your ambient environment does.
This is the kind of conversation that changes how you work. The HVAC School livestreams is back — and we're just getting started on this topic.
