One of the most common questions we get from techs is about using a voltmeter to diagnose a high voltage circuit. It's especially tricky when a tech is used to working on a low-voltage or 120V circuit, where there is a clear “hot” side of the circuit and a clear “grounded” side of the circuit. […]

When you walk up to a piece of equipment, you want to follow a process to ensure that you accomplish five things: #1 – You diagnose the fault correctly. #2 – If possible, you find the “why” of the failure. #3 – Find any other problems or potential problems with the system that can cause […]

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 […]