The Honeywell Home THM5421R1021 Grey Prestige 2-Wire IAQ Equipment Interface Module is a wall-mounted module made of plastic in a gray color. It is compatible with certain Honeywell Home THM5421 models and is designed for use with heat pumps, ductless mini split systems, central heating radiators, and packaged/rooftop air conditioners. The module has a 2-wire wire configuration and operates at 24V. It is a wireless device with one cool stage and is designed for use with a proprietary smart home protocol.
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