On an energized, intact circuit, you will read voltage across an OPEN switch when testing with a voltmeter. However, you probably won't read significant voltage across a CLOSED switch. Both sides of a closed switch are electrically identical (or at least very close). Therefore, there should be no movement of electrons between the leads of […]

One trait I've seen with good technicians is that they take their jobs VERY seriously, but they learn not to take themselves too seriously. A few months ago, I had someone tell me online that I must think I'm the A/C “god” because I'm always telling everyone the “right” way to do things. This got […]

Do you know how a solenoid valve works? Really? On the surface, I think we all understand how a solenoid valve works. The coil energizes, creating an electromagnet. That temporary magnetism lifts an iron plunger within the valve allowing refrigerant to flow. But is it really that simple? It turns out that the answer isn't […]