Offering improved design over the previous 8830 model, the AprilAire 8840 Automation Thermostat, 7-In. Color Touchscreen, WiFi, IAQ Control offers all the same great features plus a beautiful 7-inch HD color touchscreen. The thermostat can control nearly any type of HVAC unit, including humidifiers and whole-home dehumidifiers, while offering support for external sensors (one included). Featuring the unique \”SmartIAQ\” solution, this advanced Internet-connected thermostat is designed to balance all aspects of indoor air quality, including Temperature, Humidity, Air Purity and Fresh Air. The free app for iOS and Android syncs with the thermostat for seamless control. The thermostat not only offers standard 7-day programming (up to 4 events per day), but also a \”progressive recovery\” feature that can activate your HVAC equipment BEFORE a scheduled event. The thermostat also provides auto-ventilation with \”Event-Based Air Cleaning.\” Advanced capabilities: \”Heat Blast\” rapidly raises room temperature. Message center provides feedback, instructions, and service reminders. Two-part design – 3 wires to living space. Lockouts (Full, Timed, Limited). Humidifier control (auto or manual). Whole-home dehumidifier control. Dehumidify w/AC controls dehumidifier on air conditioner. Remote sensing via Support Modules (8081 and 8082, sold separately). \”Return Air\” Temperature and \”Leaving Air\” Temperature sensors. FEATURES: Universal for 3H/3C or 4H/2C heat pump. Auto changeover with deadband adjustment. Adjustable differential. Stage rate engages additional stages to achieve setpoint. Dual fuel kit allows switching between two equipment types. Balance point control to optimize heat pumps and aux heat. Compressor protection. Adjustable backlight. 3-day weather forecast. System test mode. Warranty: 5 Years. CONTENTS: Thermostat, Remote Sensor, Hardware. NOTE: Requires a computer or mobile device with Wi-Fi and a web browser. 7-inch backlit HD color touchscreen is easy to read day and night Change settings locally, online, or with the free mobile app Supports external sensors (1 included), Event-Based Air Cleaning, \”Heat Blast\” Universal design works with 3H/3C or 4H/2C heat pumps Can control humidifiers, whole-home dehumidifiers, and AC dehumidifiers