When I teach electrical basics, we do this exercise where we sit down and connect a 10-watt bulb to a power supply and through a switch. It's a SUPER SIMPLE circuit—the kind you might have learned about in a high school science class. But then I grab another 10-watt bulb and tell them to connect […]

Suction pressure, head pressure, subcooling, superheat, delta T. Taking all five of these calculations into account on every service call is critical. Even if you must do further diagnostic tests to pinpoint the problem, these five factors are the groundwork before more effective diagnostics can be done. I would also add static pressure as an […]

Modulation motors are not often seen in residential equipment, but we see them a lot in commercial and industrial applications on many different types of equipment. I see them primarily on larger burners to control the fuel firing rate, but they also control water flow through heating coils, the water level on cooling towers, and […]