Friction rate is a value located on a ductulator. We use it during the design phase of a duct system to predict the operating static pressure of a duct system. The challenge with friction rate is that it is often misapplied by folks using a rule of thumb (ROT). In order to apply friction rate properly, […]

This article is based on HVAC School’s special video for 100k subscribers. The episode features Eric Mele, Andrew Greaves, and Sam Behncke as special guests. To celebrate HVAC School’s 100,000 YouTube subscribers milestone, we've released a video on a topic that applies to all sorts of HVAC techs. Customers don’t like making callbacks, and we […]

I once had an old commercial blower assembly on a 20-ton package unit, and the bearings and pulleys were seriously shot. I was 19 or 20, and as much as I tried, I just couldn't get the rusted hunk of metal apart. I tried penetrating oil, pullers, pry bars… I knew better than to beat […]