When you first start checking your supply air with a thermo-hygrometer, you may notice that the relative humidity is REALLY HIGH. Often, the RH in a supply duct will be between 85% and 96% relative humidity on a system that is functioning as designed. The reason for this is fairly simple: In order for dehumidification […]

I was listening to someone talk about air relative humidity the other day while looking at a psychrometric chart, and he commented that the chart ends down at freezing (32°F) because “all the water freezes out of the air at that point.” I think I made this Jed Clampett face: The psychrometric chart is designed […]

I was watching this video on the HVACR Videos channel by my friend Chris Stephens, and I was impressed by how completely he diagnoses the system both visually and with his tools. Take a look. I say this all the time, but a good, efficient technician is one who sees everything and can also quickly […]