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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.

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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 ConnectionNot Provided Before Item Discontinued
Electrical Rating18 to 30 VAC
Power MethodHardwired
Batteries IncludedNo
750mV CompatibleNo
Auto ChangeoverYes
Built In Wi-FiNo
Change/Check RemindersYes
Daylight Savings Time ReadyNo
Digital-Non ProgrammableYes
Display OptionsNot Provided Before Item Discontinued
Displays Outdoor TemperatureYes
Heat Pump CompatibleYes
Indoor Remote SensorYes
LanguageEnglish, French, Spanish
Low Battery IndicatorNo
Programmable FanYes
Stages Cool2
Stages Heat4
Temperature Settings per Day4
Vacation ModeYes
Battery BackupNo
AccuracyNot Provided Before Item Discontinued
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 (4.4°C to 32.2°C); Cool: 60°F to 99°F (15°C to 37.2°C)
Terminal DesignationsR, C then RedLINK to Equipment Interface Module
Warranty OfferedYes
GEM - Case Quantity

Parts List