THM5421R1021 MFG #: THM5421R1021/U
  • Buyer STOR
  • Brand Honeywell
  • Height 9.3125 in
  • Length 1.625 in
  • Width 4.8125 in
Honeywell International Inc. / Resideo Technologies, Inc. Prestige® 4-13/16'' x 1-5/8'' x 9-5/16'', Vertical Mount, Gray, Equipment Interface Module for THX9421R5021 2-Wire IAQ Thermostat

Expand your business and offer your customers the Wi-Fi thermostats or the wireless option using the RedLINK technology for remote control of our home systems with or without an app.


  • Used On: 2-Wire IAQ Thermostat
  • Size 4-13/16 Inch Width x 1-5/8 Inch Depth x 9-5/16 Inch Height
  • Terminal Designation R, RC, RH, C, W-O/B, W2-AUX1, W3-AUX2, Y, Y2, G, A-L/A, U1, U1, U2, U2, U3, U3, S1, S1, S2, S2, S3, S3, S4, S4, A, B, C, D
  • Power Method Hardwired
  • Voltage Rating 18 to 30 Volt AC 50/60 Hertz
  • Current Rating 1 Amp Running (Cool/Heat), 0.5 Amp (Fan)
  • Number of Stages 4-Heat/2-Cool (Heat Pump), 3-Heat/2-Cool (Conventional)
  • Temperature Rating -40 to 165 Deg F
  • Humidity Rating 5 to 95 Percent RH (Non-Condensing)
  • Color Gray
  • Includes Equipment Interface Module
  • Application Gas, Oil, Electric, Heat Pump, Forced Warm Air, Hot Water, Steam or Gravity