The Xentaâ„¢ 121 zone controller is designed for fan coil and heat pump applications. This new family of controllers is part of the Vista building management system. The fan coil version of the controller can be used in both two- and four-pipe installations and configured for use with a variety of valve actuators. The heat pump controller handles both reversing and isolation valves and can be configured for up to three compressors. The controller handles heating, cooling, and secondary heating. Users can define up to three heating and cooling stages. The unit's demand-based, multifunctional fan control program handles both multistage and variable-speed fans to ensure the right amount of air for optimum comfort and greater energy efficiency. Room occupancy sensors, window contact switches, and outdoor temperature sensors can be added to the controller. The Xenta 121 also features economizer control, as well as carbon dioxide and relative humidity control. The Xenta 121 has an Exception Mode function, which allows users to pre-configure different modes to override normal control in the case of a specific event occurrence.

TAC, 1650 W. Crosby Rd., Carrolton, TX 75006; 972-323-1111 or 866-822-4636; 972-242-0026 (fax); info@tac.com; www.tac.com/us

eProduct 188