When you work on a heat pump system and want to test defrost, you can follow many different test procedures to test the board and sensors. Most involve “forcing” a defrost by shorting out pins on the board or advancing the time of the defrost initiation and installing a factory-provided pin jumper. Lots of pins […]

Whenever there is a conversation where “code” is involved, it's important to mention that codes can vary depending on the AHJ or authority having jurisdiction. It's becoming more common for governments to lean heavily on the ICC (International Code Council). In the case of HVAC/R, that is the IMC (International Mechanical Code), and in the […]

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 […]