Dissimilar metals, like aluminum, copper, brass, and steel, are some of the main metals one may experience in their trade, and few people are comfortable working with dissimilar metals. They don’t trust their brazed joint, or they are afraid of melting away material. To put some of the nerves of those in the field at […]

If you work in refrigeration, you may have heard the term “hot pull down.” This phrase describes a condition where the load on the evaporator is above design due to the box temperature or the temperature of the product in the box being higher than it would normally be. My grandpa called me a few […]

Evaporator temperatures below 32° are common and acceptable in refrigeration; that's why there is a defrost sequence. In a heat pump running in heat mode, it's the same; freezing is a part of the process, and defrost is necessary. In comfort cooling, we can't allow the evaporator to get below 32°, or it will freeze. […]