There is a big move in residential and light commercial HVAC toward measuring static pressure regularly during commissioning, service, and maintenance. Don't get me wrong… Measuring static pressure is VERY important. The challenge comes in when techs begin taking measurements without understanding where to take them, what they mean, or worse: they use measurements as […]

Airflow, airflow, airflow… When we set up and commission comfort cooling and heating systems, we need to pay more attention to airflow before worrying about the fancy controls or the refrigerant circuit. So, as a thought exercise, let's consider a typical 2-ton, straight cool, TXV residential system and think through what happens when we alter […]

Basic Compressor Functions The compressor's job is to circulate refrigerant through the system by means of vapor compression, similar to the way your heart moves blood through your circulatory system. Refrigerant circulation is measured in lbs/min or lbs/hour; this is called mass flow rate—the mass flow rate changes depending on the density of the refrigerant […]