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Honeywell Prestige with IAQ remote YTHX9421R5077

Prestige redefined design with their high-definition color system and now, Prestige IAQ does the same, with easy installation & control from a one device. But that’s not all. Prestige IAQ connects you to customers with Customizable Service Reminders.

Key Features


  • Large, easy-to-read full color display shows current indoor temperature and humidity, temperature setting, date and time on the home screen. Also displays outdoor temperature and humidity on home screen (if wireless outdoor sensor is installed)
  • Controls multistage equipment, humidification, dehumidification and ventilation all with only 2 wires at the thermostat location
  • Customizable Service Reminders allows the contractor to have automated messages direct homeowners to a screen with the contractor’s full-color company logo, phone number and website.
  • Change Reminders to inform it is time to replace air filter, humidifier pad or ultraviolet bulb or batteries in RedLINKâ„¢ connected devices.
  • Adjustable backlight level allows thermostat to be on full brightness at all times or dim to the brightness level of choice when the thermostat is not being used
  • Interview-Based Programming wizard to easily and confidently schedule thermostat temperature and times
  • USB Port allows downloading of installer settings to quickly and consistently perform setup of thermostats in similar applications
  • USB Port allows easy setup of dealer logo and contact information on thermostat screen
  • Real-Time Clock keeps time during power failure; automatically updates for daylight saving time
  • Precise Temperature Control (± 1 F) for reliable and consistent temperature
  • Multiple HOLD options allows modification of schedule as needed
  • RedLINKâ„¢ Enabled to communicate with compatible wireless devices


  • Application: Up to 4 Heat/2 Cool Heat Pumps,Up to 3 Heat/2 Cool Conventional Systems
  • Includes: THX9421R5013 Prestige IAQ 2-Wire Thermostat, THM5421R1013 Equipment Interface Module, REM5000R1001 Portable Comfort Control, C7089R1013 Wireless Outdoor Air Sensor and two C7735A1000 Duct Sensors
  • Electrical Ratings: 18 to 30 Vac
  • Operating Humidity Range (% RH): 5 to 90% RH, non-condensing
  • Programmability: 7-Day Multiple Day Programming or Non-Programmable
  • Setting Temperature Range (F): Heat: 40 F to 90 F; Cool 50 F to 99F
  • Humidification Setting Range: Cooling: 40 to 80% RH. Heating: 10 to 60% RH.

Technical Documents

Operating Manual

Installation Guide

  • Honeywell Prestige with IAQ remote YTHX9421R5077