Theory and troubleshooting using short modules packed with images to make learning quick and easy.
Lessons on air conditioning systems and cooling operation. For students and working technicians learning cooling theory and troubleshooting.
Air conditioners and walk-in coolers do not create cold. They remove heat from an area where you do not want it and dump it somewhere where it does not matter. To move that heat, the system circulates refrigerant through a closed loop of copper tubing. By changing the pressure of the refrigerant, the system forces…
A field guide to avoiding premature valve condemnation and mastering the 4-way mechanism. The reversing valve is the heart of a heat pump's ability to provide year-round comfort. It is the component responsible for seasonal switching, physically redirecting refrigerant flow to turn an air conditioner into a heater. For many technicians, however, the reversing valve…
Mastering the Vitals of the Refrigeration Cycle If you want to know what is actually happening inside a refrigeration system, you have to look past the pressures. Gauges are a great start, but they only tell half the story. To truly diagnose a system, you need to understand the relationship between temperature and pressure. Superheat…
Take any chance you have to skip connecting refrigerant gauges to a system. Each time you attach your gauges, you remove a small amount of refrigerant from the system through your hoses. The longer the hoses, the more charge that's lost. After a few times of doing this, you might end up chasing a leak…