What is a requirement for the labeling of heat recovery ventilation systems?

Labeling heat recovery ventilation systems according to UL 1815 is a critical requirement because UL (Underwriters Laboratories) standards ensure that the devices meet safety and performance criteria. UL 1815 specifically focuses on the testing and classification of such systems to guarantee that they operate safely and effectively under specified conditions. Compliance with this standard provides assurance to users and installers that the system adheres to recognized safety practices, which is crucial for any mechanical equipment used in residential and commercial applications. This labeling helps in both the identification of the system and verifying its compliance with safety regulations.

In contrast, other aspects, such as installation costs, heat recovery efficiency, and manufacturer details, are important but do not directly relate to the specific safety recognition that UL 1815 provides. Therefore, while they may contribute to the overall understanding of the system's performance and background, they are not the primary focus of required labeling standards.