Honeywell Equipment Interface Module Controls

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Manufacturer Part Number: THM5421R1021

The THM5421R1021 Equipment Interface Module controls up to 4-stages of heat and 2-stages of cool in a heat pump system and up to 3-stages of heat and 2-stages of cool in a conventional system.

Key Features

  • Three sets of Universal IAQ contacts to control humidification, dehumidification, and ventilation.
  • Used with all versions of Prestige IAQ Thermostats and the New RedLINK VisionPRO Thermostats.
  • Four sensor inputs for wired sensors or dry contact devices


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