What Affects Heat Transfer

Good evening plumbing fans! In today's post we will dive into learning more about heat. We will cover what heat is, what temperature is, and what is behind heat transfer. Ready?

Heat is basically energy, not in electrical, chemical or mechanical form, but rather in thermal form. It is measured in British thermal units, which measure the amount of heat required to raise 1 pound of water by 1 Fahrenheit. 

Now, what is temperature? Temperature measures the vibrations of particles in matter. Thus, heat is our perception of the intensity of vibrations.

Now, how does heat travel from one area to another? This following point is very important: heat moves from areas of higher temperature to areas of lower temperature. Yes, indeed, without a difference of temperatures, there is no heat transfer.  Thus, if two areas have similar temperatures, there will be no heat transfer. If the difference between those two areas is small, the transfer will be small too. If the difference in temperature between those two areas is large, then the transfer of heat will be fast. 

In hydronic systems, a heat source (the boiler) creates heat that moves to metal walls of the boiler, to the metal walls of the heat exchanger to the water that then transfer the heat to the walls of the heat emitter, which then transfer the heat to the air. From their we can follow the transfer of heat to the walls and then to the outside air. Indeed, the heat follows the direction to the cooler metal and other substances/materials.

One more thing to point out is that there is heat (the amount of heat in an object) measured in BTUs, and there is heat rate, the rate at which heat moves into or out of an object.