Honeywell, Inc. THM5421C1008 Equipment Interface Module for

SKU: THM5421C1008
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Equipment Interface Module for
• Advanced dual-fuel control.
• Three wires to the living space allows for easy equipment upgrade without having to run additional thermostat wire.
• Thermostat connects with Equipment Interface Module or EnviraZONE panel to control temperature, humidification, dehumidification and ventilation from a single point in the home.
• Automatically raises humidity levels throughout all rooms in the home, moisturizing air to prevent symptoms of dryness and to protect hardwood flooring and woodwork.
• Removes air pollutants by exchanging the stale air in a house with fresh, filtered air better than having an open window.

Cool Current1.0 A running
Fan Current0.6A running
Discharge SensorYes, optional
OverviewThe VisionPRO IAQ touchscreen universal programmable thermostat provides electronic control of 24 Vac heating and cooling systems in addition to humidification, dehumidification and ventilation all with just 3 wires to the thermostat.
Heat Current1.0 A running
Terminal Designations1, 2, 3, C, R, Rc, Rh, R, W1-O/B, W2-Aux, W3-Aux2, Y, Y2, G, L, Out1, Out2, In1, In2, Dats1, Dats2, Hum1, Hum2, Dhm1, Dhm2, Vnt1, Vnt2
StagesUp to 4 Heat/2 Cool Heat Pump
Outdoor SensorYes, optional
Remote SensorYes, optional
Operating Humidity Range (% RH)5 to 90% RH, non-condensing
IncludesEquipment Interface Module Only
ApplicationHeat/Cool or Heat Pump with Auxiliary Heat
ColorPremier White®
Power MethodHardwired
Dimensions (in.)7 1/4 in. high x 4 1/2 in wide x 1 3/8 in deep
Dimensions (mm)185 mm high x 116 mm wide x 34 mm deep
Electrical RatingsTHM5421 is rated 20 to 30 Vac
Frequency60 Hz
CommentsIncludes Humidification Control with or without Frost Protection, Dehumidification using Whole House Dehumidifier or Air Conditioning with High or Low speed fan, Advanced Patented Ventilation Control and Advanced Dual Fuel Heat Pump Control.
Used WithTH9421 VisionPRO IAQ Thermostat
Voltage20 to 30 Vac
List Price166.27

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