The second law of thermodynamics puts the first law into context and establishes entropy as a concept. We can simply define entropy as a state of disorder that can only increase or remain the same in natural processes. Processes in which entropy remains the same are reversible, but ones that result in an entropy […]

This article was written by Gary McCreadie from “HVAC know it all.” You can learn more about Gary and his tips and growing community on Facebook and LinkedIn. What is an economizer?  Simply put, it is a mechanical device designed to reduce energy consumption, whether it be fuel, electricity, or other. According to Wikipedia, the first […]

Fenestration is a fancy architectural term that means “openings in the outside of the building.” You will see this word a lot when you read ACCA manual J or when you are doing a manual J load calculation. Fenestration loads include heat losses and gain through windows, doors, skylights, etc., and they can make up […]