Over the years, I have heard technicians say that refrigerant can wear out or “lose its blend” by sitting in a tank. Refrigerant does not wear out or “lose its blend”… at least not like that. What can and does happen is called “fractionation.” Refrigerant blends are composed of a mix of refrigerants with different […]

I am in the midst of testing the accuracy and repeatability of different types of airflow measurements for techs in search of the most practical methods for different applications. A commonly taught method for measuring airflow is the temperature rise method, where you use a heat source that produces a set number of BTU/h, such […]

In commercial HVAC, you will find several different types of multi-stage evaporator coils: intertwined (shown above), horizontal face split (one coil on top of another), and vertical (side by side). When staging a horizontal evaporator, pay attention to ensure that stage #1 is on the bottom and stage #2 is on the top. If stage […]