Red Seal Refrigeration and Air Conditioning Mechanic Practice Exam

Latent heat refers to the energy absorbed or released by a substance during a phase change without a corresponding change in temperature. This process can occur when a substance transitions between solid, liquid, and gas phases, such as when ice melts into water or water vapor condenses into liquid water. During these changes, heat energy is either taken in (absorbed during melting or vaporization) or released (during freezing or condensation), but the temperature of the substance remains constant throughout the phase transition.

Understanding latent heat is crucial in refrigeration and air conditioning systems, as it plays a significant role in how these systems operate. For example, in refrigeration, refrigerants absorb latent heat as they evaporate in the evaporator coil, cooling the surrounding air, while they release latent heat when they condense in the condenser coil.

The other options describe different aspects of heat transfer, such as sensible heat or heat loss mechanisms, but they do not accurately define latent heat, which is specifically concerned with phase changes of substances.