When I was a green tech, I was really big into showing up all the other techs by doing THE BEST cleaning I possibly could. One of my favorite things to do was to clean the condenser until it was SPOTLESS inside and out. The only issue was that I really liked using that brown […]

Does setting a thermostat too low cause an air conditioning system set in cool mode to freeze? The answer is no, at least not directly. However, low evaporator load (low return temperature or low airflow) and low outdoor ambient temperature can lead to evaporator coil freezing. Low indoor setpoint can lead to low return air […]

When a system has abnormally high head pressure (high condensing temperature over ambient) and compression ratio, one of the easiest things to look for is a dirty condenser coil. More often than not, that will be the cause. However… There is another category of issues that can cause high condensing temperature (high head pressure), but these […]

Carter Stanfield, a co-author of Fundamentals of HVACR, talks about the entire refrigeration circuit. He also explains how to read and plot a pressure-enthalpy diagram. The refrigeration circuit has four main components: evaporator, compressor, condenser, and metering device. When teaching, Carter likes to explain that boiling is a cooling process and condensation is a heating […]