Nathan Orr Archives

Deburring copper tubing (often called reaming) is the practice of running a blade around the inside of tubing after you cut it to remove the burr edge from the inside. It's an important practice and should be performed whenever possible. Deburring reduces turbulence inside the lines, as burrs can cause turbulence. HOWEVER… YOU MUST […]

What is the Difference Between ACH & ACH50?

This photo is of a blower door test we performed at my own house using a Retrotec blower door. You will notice the 15-passenger van outside the window, which is a dead giveaway. A blower door is used to measure the tightness of a building and is often discussed in terms of an ACH50 number. […]

Which Valve Do I Open First?

Testo 557 vacuum gauge and Appion core removal tools shown I've had a change of heart. Back in the early 2000s, during the big construction boom, I did many system startups on residential units for a large company I worked for. When installers ran the line sets prior to startup, they weren't always very careful […]

Nitrogen and Torch Use

Rooftop Unit Install and Changeout Considerations

Hard Lessons w/ Roman, Tim D., Nathan O. and ELK

Join industry veterans Tim De Stasio, Roman Baugh, Eric Kaiser, and Nathan Orr as they share their most memorable HVAC lessons learned the HARD WAY. This unfiltered conversation from the 7th Annual HVAC/R Training Symposium reveals the real stories behind costly errors, dangerous situations, and valuable HVAC training moments that shaped their careers. What […]

Residential vs. Commercial HVAC Sales

In this candid conversation, Nathan and Bryan dive deep into the often-misunderstood world of sales in the construction and HVAC trades. Nathan, who has transitioned from fieldwork to spending roughly 60% of his time in sales, offers a unique perspective on why sales professionals are necessary despite the skepticism they face from tradespeople. The […]

Humidity, Airflow, and Refrigeration

In this episode of the HVAC School podcast, Bryan and Nathan dive deep into the challenges of humidity control in grocery stores and other refrigerated environments. While the conversation takes several entertaining detours (including discussions about morning radio shows, Indian weddings with elephants, and imaginary lava-heated homes), the core content provides valuable insights for […]