What configuration is used for a heat pump installation added onto an existing system?

The choice indicating a coil in the return air plenum is appropriate for a heat pump installation added to an existing system because it allows the heat pump to effectively utilize the air that is already being circulated within the home. By placing the coil in the return air plenum, the heat pump can enhance the system’s efficiency by directly conditioning the air that is returning to the system. This configuration enables optimal heat exchange between the refrigerant in the coil and the air being recirculated, improving overall thermal comfort and energy efficiency.

Additionally, the return air plenum location takes advantage of the existing ductwork, reducing installation complexity and costs compared to other configurations that might require significant adjustments or separate ducting. This integration helps maintain the system's balance while providing effective heating or cooling as needed.

Understanding the context of installation configurations highlights the practicality and efficiency of using a coil in the return air plenum, making it a logical choice for retrofitting a heat pump into an existing heating and cooling setup.