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Wireless Thermo-Hygrometer with Ventilation Recommendation BEL-AIR


  • Simultaneous check of indoor and outdoor climate
  • Ventilation tips to improve the indoor climate
  • Outdoor temperature and humidity via transmitter
  • Coloured comfort-level zones for a healthy indoor climate
  • Max.-min. values

Item number:




Product specification

Window open or closed? Finding the ideal indoor climate is not so easy and ventilation isn't always the first choice. Depending on the weather, the air quality may even deteriorate. The "BEL-AIR" wireless thermo-hygrometer from TFA is the practical help you need.
Internal sensors measure the indoor temperature and humidity and display the quality of the indoor air on the coloured scale.
At the same time, the outdoor transmitter determines the temperature and humidity in the open air and it is calculated whether the room humidity rises, remains the same or decreases by opening the windows. In this way, you can immediately take the required steps, ensure a comfortable and healthy indoor climate and prevent the formation of mould.


  • Simultaneous check of indoor and outdoor climate
  • Ventilation tips, when opening or closing windows will improve the indoor climate
  • Wireless transmission of outdoor temperature and humidity via transmitter
  • Indoor temperature and humidity with coloured comfort-level zones for a healthy room climate
  • Max.-min. function
  • Registered TFA design

TFA Quality mark:

  • Swiss Precision Sensor
  • IT Instant Transmission
  • Registered TFA Design Patent

Product information for download:

Technical data

Measuring range temperature outdoor-40...+60°C (-40...+140°F)
Delivery contentsBase station, thermo-hygro transmitter, instruction manual
Measuring range humidity outdoor1...99%
Maximum range100 m
Transmitter included in delivery30.3187.IT
Transmission frequency868 MHz
Measuring range temperature indoor-10...+60°C, (+14...+140°F)
Measuring range humidity indoor20...95%
AssemblingTo be hung or freestanding
Power consumptionBatteries
Batteries2 x AAA 1.5 V (base station), 2 x 1.5 V (transmitter)
Batteries includedNo
Dimensions(L) 95 x (B) 20 (65) x (H) 158 mm
Weight119 g