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 […]

First, here's a quick summary of the role of oil in the refrigerant circuit: The compressor requires oil for the lubrication of the moving parts in the compressor. We would keep 100% of the oil in the compressor if we could. However, that is generally unrealistic. So, we need to utilize oils and oil strategies […]

In residential, most techs and installers size the suction (vapor) and liquid lines to the stubs on the equipment. In larger built-up systems, sizing the piping is rarely the responsibility of the technician. But what happens if we show up to a job where the lines cannot be (reasonably) replaced because the size is different? […]