This is a basic overview of the refrigeration circuit and how it works. It isn't a COMPLETE description by any means, but it is designed to assist a new technician or HVAC/R apprentice in understanding the fundamentals. First, let's address some areas of possible confusion:  The word “condenser” can mean two different things. Many in […]

Have you ever seen a low-voltage transformer like the one shown above? It has multiple input (primary) taps for a good reason. It is common to find three-phase and single-phase equipment rated to operate on both 240v and 208v power. That is because three-phase power can either be 208v leg to leg when the building […]

Proving flame is an important part of the gas firing sequence. Without proof of flame, you risk dumping unspent gas into the heat exchanger, resulting in an explosion. There are many ways to “prove flame,” but we are focusing on the flame sensing rod (flame rectification) method here. Here are the facts: Flame sensing rods, […]