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Honeywell YTHX9421R5077 - Prestige® IAQ 2.0 HD 2-Wire Comfort System Kit. RedLINK™ enabled 4 Heat/2 Cool

Item: YTHX9421R5077
MFR: YTHX9421R5077/U
This product is no longer available for purchase.
Comparable Product:


Honeywell Prestige IAQ 2.0 HD 2-Wire Comfort System Kit. RedLINK enabled 4 Heat/2 Cool
Includes 2-wire HD color Thermostat, IAQ Equipment Interface Module, Portable Comfort Control, Wireless outdoor sensor and 2 Duct Sensors for diagnostics. Selectable for Residential and Commercial. Up to 4H/2C heat pump and up to 3H/2C conventional.
  • Delta T Alerts and Diagnostics informs customers when their system is not operating as expected
  • Configurable for Residential or Light Commercial applications
  • Diagnostics that work on every brand, and every efficiency of equipment
  • User Interaction Log provides a searchable history of setting changes
  • Assignable output/input/sensor relays trip pre-packaged or customized alerts
  • Configurable staging options
  • Complete dual-fuel and IAQ control with only two wires
  • Customizable service reminders on screen
  • Displays outdoor temperature and humidity
  • Patented, interview-based programming and installer set-up
  • USB port for installer setup options and dealer information transfer
  • RedLINK-enabled to work with: RedLINK Internet Gateway / Total Connect, Portable Comfort Control, Wireless Outdoor Air Sensor, Wireless Indoor Air Sensor, TrueSTEAM and TrueZONE Panels
  • Displays outdoor temperature and humidity when paired with an outdoor sensor
  • Up to 4H/2C Heat Pump & 3H/2C Conventional
  • 5-Year warranty


NameHoneywell YTHX9421R5077 - Prestige® IAQ 2.0 HD 2-Wire Comfort System Kit. RedLINK™ enabled 4 Heat/2 Cool
Gemaire Item NumberYTHX9421R5077
Manufacturer Product NumberYTHX9421R5077/U
SKU - PIM Number1389112013852
ERP Number306624
Unit of MeasureEA
Weight1.3 Pounds (Lb)
Length3.5 Inches (In)
Width7.0 Inches (In)
Height5.3 Inches (In)
Country of OriginMEX
Voltage18-30 VAC
Electrical Rating18 to 30 VAC
Power MethodHardwired
750mV CompatibleNo
Auto ChangeoverYes
Built In Wi-FiNo
Change/Check RemindersYes
Digital-Non ProgrammableYes
Displays Outdoor TemperatureYes
Heat Pump CompatibleYes
Indoor Remote SensorYes
LanguageEnglish, French, Spanish
Programmable FanYes
Stages Cool2
Stages Heat4
Temperature Settings per Day4
Vacation ModeYes
IncludesTHX9421R5013 Prestige IAQ 2-Wire Thermostat, THM5421R1013 Equipment Interface Module, REM5000R1001 Portable Comfort Control, C7089R1013 Wireless Outdoor Air Sensor and two C7735A1000 Duct Sensors
Ambient Temperature Range32°F to 120°F (0°C to 48.8°C)
ApplicationUp to 4 Heat/2 Cool Heat Pumps or Up to 3 Heat/2 Cool Conventional Systems
Comments/NotesTri-Lingual Display (selectable for English, French or Spanish)
Dual Transformer CompatibleNo
Fan SwitchingYes
For Use WithRedLINK™ enabled thermostats and accessories
Operating Humidity5 to 90% RH, non-condensing
Operating Temperature Range32°F to 120°F (0°C to 48.8°C)
Removable InterfaceNo
System SwitchingYes
Temperature RangeHeat: 40°F to 90°F; Cool: 50°F to 99°F
Terminal DesignationsR, C then RedLINK to Equipment Interface Module
Warranty OfferedYes
GEM - Case Quantity

Parts List

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