Measuring airflow is easy. Measuring airflow accurately is quite a bit more difficult. In many cases, when we as technicians measure airflow, we are trying to get to the almighty CFM (cubic feet per minute) volume measurement. You can take CFM readings fairly easily with a hood, like the Testo 420, but even a hood […]

As we discussed in an earlier podcast, a TXV maintains a specified and constant superheat at the evaporator coil outlet. It does this through a balance of forces between the bulb pressure (opening force), equalizer pressure (closing force), and spring pressure (closing force). We can actually adjust the spring pressure on some valves. But why […]

Most techs know that you shouldn't fill a recovery tank more than 80% with liquid-based refrigerant. Many know that the WC rating stands for “water capacity.” So, you need to adjust for the density of the actual refrigerant rather than just using 80% of WC. I hope most of you know that the TW marking […]