First, let's state the obvious and clear the air a bit. The photo above is SUPER CHEESY! But this story is about three bad techs who don't know it, so a photo of three models clearly posing in clean clothes makes as good a proxy for a bad tech as anything else. First off, I'm not […]

Service valves are so basic, and we see them with such regularity that we can miss them altogether. Before I give the tips, I want to address the tech who tells the customer it was “probably the service valve” or “the caps were loose” as a plausible reason for a leak without actually making a […]

When you walk up to a piece of equipment, you want to follow a process to ensure that you accomplish five things: #1 – You diagnose the fault correctly. #2 – If possible, you find the “why” of the failure. #3 – Find any other problems or potential problems with the system that can cause […]

Carter Stanfield, a co-author of Fundamentals of HVACR, talks about the entire refrigeration circuit. He also explains how to read and plot a pressure-enthalpy diagram. The refrigeration circuit has four main components: evaporator, compressor, condenser, and metering device. When teaching, Carter likes to explain that boiling is a cooling process and condensation is a heating […]