For years, Testo has been the first choice when it comes to high specification humidity transmitters for drying processes and critical ambient condition monitoring. With the new Testo 6621, this sensor and electronics know-how is now available in a low cost package for more general HVAC building control applications.
The attractive architect friendly design is the perfect solution for monitoring temperature and humidity in buildings whether mounted on a wall or in a ventilation duct.

Operators, facility managers, and plant engineers recognise the importance of long-term measurement stability. Undesirable ambient conditions as well as higher operating costs are incurred if humidity measurement goes out of control. The long term stability and accuracy of the industry leading Testo humidity sensor at the heart of the 6621 has been proven time and time again and demonstrated by numerous independent laboratory studies.

Installing the Testo 6621 is as easy as 1,2,3 thanks to the intelligent design of the transmitter housing. Commissioning large scale projects is fast and straightforward with Testo’s P2A software which allows easy set up and configuration of units and output scaling.