American Aldes patented* Zone Register Terminals (ZRT®) are designed to introduce flexibility and on-demand control to central ventilation systems. Used in both large and small systems, the ZRT-S zonally regulates ventilation without the need for individual fans. Each ZRT-S is a combination grille, register box, control damper, and optional flow regulator(s). This unique combination provides up to four different control schemes without the need for expensive pneumatic, electronic, or DDC control systems.
By replacing static grilles in large central continuous supply systems, the ZRT-S-1 model provides on-off control for on-demand ventilation. The optional Constant Airflow Regulator (CAR-II) can be installed in the ZRT-S-1’s extended duct collar to place a maximum flow limit on each terminal.
The ZRT-S-2 model can be used for combination low-flow indoor air quality ventilation and on-demand high-flow spot ventilation, such as bathroom fans, using the same central fan system. This is achieved by integrating a minimum Constant Airflow Regulator (CAR-II) directly into the damper sub-assembly. With the damper completely closed, the factory-calibrated CAR-II will still allow steady, low-continuous ventilation during fan operation. When other ZRT-S are opened for on-demand control of spot ventilation, the closed ZRT-S-2 will maintain the specified low-continuous rate through the minimum CAR-II. By opening the ZRT-S-2’s control damper, the low-flow CAR-II is removed from the air stream, allowing either controlled (optional using a second CAR-II) or full maximum-boost ventilation.