Air Conditioning Repair Certification (ETI) Practice Exam

The process of adding heat to refrigerant in a vapor state after it has evaporated is called superheat. During superheating, the refrigerant absorbs additional heat beyond its boiling point, causing the temperature of the vapor to increase without any change in its mass or state. This is a critical part of the refrigeration cycle, especially in systems utilizing vapor-compression refrigeration. Superheating ensures that the refrigerant vapor entering the compressor is in a vapor state, preventing compressor damage and improving efficiency. If the refrigerant were to contain liquid droplets when it enters the compressor, it could cause hydraulic issues or even mechanical failure. In contrast, latent heat refers to the heat energy required for a phase change to occur, like from liquid to vapor, without a temperature change, while sensible heat involves temperature changes in a substance without a phase change. Condensation is the process of the refrigerant changing from a vapor back to a liquid, releasing heat in the process. Understanding these processes in refrigeration systems is key to effective troubleshooting and repairs.