In HVAC systems, liquid and vapor will exist at the same time and place. We call that condition saturation, or we say that the refrigerant is “at saturation.” Phase changes occur in the evaporator and condenser, so these are spots where liquid and vapor coexist while the system is running. Saturated conditions occur whenever liquid […]

Photo by Stephen Rardon I hear it all the time. Someone will talk about undesired condensation on an air handler cabinet, on a supply air duct, in a ventilation duct, or on a vent like the one above. In reply, someone will inevitably say, “Condensation occurs where hot meets cold.” Early on in my career, […]

Thought Experiment #3 – The Start Winding Has No “Inrush” with a run capacitor only  The name “start winding” is an antiquated term for the single-phase residential industry. It came from the days when CSIR (capacitor start, induction run) motors were still used commonly. In a CSIR motor, the start relay removes the start winding […]