When someone says there is no such thing as “cold,” only the absence of heat, you can point out that while cold is the absence of heat… absolute zero is the definition of COLD. The third law of thermodynamics addresses the absence of heat and what that means for entropy. It implies that absolute zero […]

Many in our industry can misunderstand the differences between temperature and heat, although these are related. Substances are composed of many moving molecules that change their speed as they release or gain heat. When we heat a glass of water in a microwave, its molecules start to move more quickly. The velocity increase results in […]

In residential air handler/fan coils, it is common to use a high-voltage interlock between the blower and the electric heat strips to ensure that the blower comes on whenever the heat is on. The problem is that it CANNOT work the other way around where the heat comes on with the blower. Heat strips are […]