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GFX4 Automatic Digital Humidistat (Controls the Furnace Blower Motor)

GFI#: 7170
Price: $212.78


Ref # GFI # Part Name Image Qty Req'd Price
7021 80.jpg 1 $72.44
Qty: Add


  • Voltage:  18-30 VAC, 60 Hz
  • Switching load:  1 amp maximum 30 volt
  • Dimensions (inches):  3 3/4 H x 31/2  W
  • Outdoor Sensor Length (feet/meters):  200 / 61
  • Accuracy:  RH (77°F/25°C) 10%-90% +/-3%RH
  • Accuracy drift per year:  +/- 0.5%RH
  • Accuracy indoor temperature:  +/- 2°F / -1°C
  • Relay close:  setting -1%RH
  • Relay open:  setting =1%RH
  • Auto mode:
    • Control range:  10% - 60%RH
  • Manual mode:
    • Control range:  10% - 75%RH
  • Warranty (years):  1


  • The GFX4 includes all the same features as the GFX3 but will also control the furnace blower motor.  Maintain more consistent humidity levels with the GFX4.
  • Automatically adjust your humidity level by reading outdoor temperatures when you install the included Outdoor Sensor.  
  • OR, control your humidity levels manually. Simply don't install the Outdoor Sensor.
  • Features easy-to-read and understand LCD Readout Display.
  • You can calibrate the GFX3 in the field to match existing appliances in the home.
  • The GFX3 is of the most accurate in the market:  RH (77°F, 25C) 10%-90%±3%RH.
  • Mount the GFX3 on in the wall or directly in your duct.  The GFX3 reads humidity levels accurately no matter the installation, due to extensive venting that more accurately samples the room's air.
  • The GFX3 boasts an extended humidity range:  from 10% to 75%.  That means the GFX3 is ideal for humidors or wine cellars, and for older turn-of-the century homes in Northern climates alike.
  • No special wiring is required to install the GFX3.  Use any wire you may have in your truck and the GFX3 will perform as promised.
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