I get questions all the time about performing “load calculations” and “rules of thumb” or how to do it properly. This article isn't about load calculation, but the only good answer is to find a quality ACCA-approved Manual J software and get used to using it. You may have heard from others in the field […]

I got in one of these tiny torches the other day to experiment with brazing aluminum in tight spots, and one of the techs walked in and asked, “What type of torch is that?” I answered, “It's oxy/acetylene.” He picked it up and looked at it a bit, then asked, “Does that get hot enough […]

The most common method to defrost appropriately in refrigeration involves both time for initiation and a combination of time and temperature for defrost termination (ending defrost). But why can't we just use temperature or time alone? (You may wonder.) Imagine a common freezer with a designed box temperature of -10°F and a coil temperature of […]