We had a class with our refrigeration techs, and the topic of leaking and bypassing service “angle” valves and ball valves came up. One of the techs pointed out that most valves recommend loosening the top nut on ball valves and the packing nut on angle valves before turning the stem for maximum longevity of […]

In HVAC, we work with thermocouples for temperature measurement all the time, but we may not understand the difference between a thermocouple and other types of temperature measurement sensors. A thermocouple is just two different types of metal connected at a “junction” that generates a small voltage with a temperature change. Older furnaces would often […]

Have you ever thought about the relationship between velocity and pressure? If you think about a fluid being forced through a small orifice, you can fairly easily picture the fluid speeding up as it goes through the orifice. However, did you also know that the surrounding static pressure DECREASES at the point of high velocity? […]