The Siemens Series RDY2000 Commercial Room Thermostat is designed for light commercial HVAC systems that utilize 24 Vac control circuitry. It is compatible with forced air, hydronic, or steam systems fired by gas, oil or electricity. The thermostat can control up to three stages of heating and three stages of cooling in a conventional system and heat pumps systems with up to two compressors and two stages of auxiliary heat. The RDY2000 can interface with remote sensors and devices to completely manage all aspects of room comfort, including temperature, humidity, and air quality. Features: Compatible with conventional and heat pump applications Controls conventional systems with up to three stages of heating and three stages of cooling Controls heat pump systems with one or two compressors and up to two stages of auxiliary heat On-board temperature and humidity sensors Specifications: Manufacturer: Siemens Building TechnologyManufacturer Part Number: RDY2000Product Type: ThermostatType: Programmable Display: LCD Backlit Control Output: 3H/3C Supply Voltage: 24 VAC Dimensions: 5.1" x 6.1" x 1.75" Weight: 0.92 LbInst. Manual