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. […]

There is a lot of misunderstanding about the HSO (hard shut-off) or “non-bleed” TXV (thermostat expansion valve) and what makes it shut off, why it exists, and how it “magically” opens. Once you understand the forces inside the valve, it is quite simple, obvious, and sadly devoid of any magic. The Three Forces  The TXV […]

Marley was dead, to begin with. There is no doubt whatever about that. That's the way Charles Dickens begins his “A Christmas Carol,” one of the most well-known pieces of literature in the modern world. A short story that can be read aloud in a few hours has to start memorably, and this one certainly […]