Short 12 – The First 4 Rules to Learn (Podcast)

Many techs have said, “That's the first thing you should have learned in school.” In today's short podcast, Bryan talks about the four rules that have his vote for the first things to learn in school.

These four rules don't just apply to HVAC work; they apply to science and the world as a whole. They describe how the forces in our world work in our HVAC careers and our everyday lives.

The overarching theme of these rules is that high goes to low. Gravity is the prime example of this rule; if you drop something from a high place, it will fall to a lower place. There is a potential energy difference between high and low, whether you apply that to a ball rolling down a hill, voltage, or a sine wave.

The first rule is that high pressure goes to low pressure. The compressor applies lots of pressure to the low-pressure refrigerant inside of it.

The second rule is that high temperature goes to low temperature. We transfer heat from the inside of the house to refrigerant inside the evaporator coil. (Remember: temperature is an AVERAGE measure of molecular activity.)

The third rule is that high voltage goes to low voltage. Electrons move from the higher energy state to the lower energy state.

The fourth rule is that high humidity goes to low humidity. For example, two air masses with different humidity contents can be separated by a cloth. The higher-humidity air mass will diffuse some of its moisture across the cloth to the lower-humidity air mass. This process creates a stasis across the two air masses.

Everything in the world tends towards equilibrium.


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