Testo 760 Category IV Multimeter I was standing at a booth at the HVAC Excellence Educators conference, and an instructor walks up, grabs a meter, and asks me, “What's the difference between a category 3 and a category 4 meter?” Well, I really wasn't sure, but I knew that the category 4 meter is rated […]

UPDATED VERSION AS OF 4/1/2020 As HVAC contractors, we are tasked with keeping staff and customers safe during the outbreak, and we are relied upon to provide some guidance to customers about how to protect themselves against the virus in the air. For employers and employees looking to navigate the new FMLA/FFRCA legislation, we put […]

I got this question via email (edited slightly for length): Some things I've done because I've been taught to do them yet I don't know why I do them. One of those things is putting a jumper between w1/e and w2. Sometimes, in the case of a Goodman for example, I've been taught to combine […]