High-efficiency HVAC systems tend to produce excessive what?

High-efficiency HVAC systems are designed to operate more effectively and utilize energy more efficiently, which often leads to a significant byproduct: condensate. These systems, particularly those that incorporate cooling features, dehumidify the air as they cool, resulting in the production of water from moisture in the air. This condensate must be properly managed through adequate drainage to avoid issues such as mold growth or water damage within the system or building.

In contrast, noise, vibration, and heat are typically concerns associated with operational inefficiencies or specific mechanical issues rather than a common byproduct of high-efficiency systems. While high-efficiency models can be quieter and more stable, they are more prone to creating condensate as part of their efficient operation cycle, making this the most pertinent choice in the context of the question.