The second law of thermodynamics puts the first law into context and establishes entropy as a concept. We can simply define entropy as a state of disorder that can only increase or remain the same in natural processes. Processes in which entropy remains the same are reversible, but ones that result in an entropy […]

I was walking around at the AHR conference today, and I stopped at the booth of a popular hard start kit manufacturer (especially popular with white-shirt sales techs). I listened to the guy behind the booth “training” some municipal maintenance techs on the use of his hard start kit. (To be fair, I actually think […]

When evacuating, the FASTEST way is to use two large-diameter hoses connected to two core removal tools and the cores removed. These hoses are then connected to the pump using a tee or evacuation “tree.” However, when you only have one large hose, another acceptable method is to connect the large hose to the suction […]