The Testo 635-1 Thermo-Hygrometer is a universal device for measuring air humidity, material balance moisture and the pressure dew point in compressed air systems.
For analysing the humidity at roofs and walls the testo 635 shows directly the dew point distance between the room air and the wall surface.
For testing the pressure dew point in compressed air systems precision sensors up to -60°C tpd are available.