
The new testo 860i wireless thermal imager for smartphones: Smart solution for fast and precise measurements for
contractors and in many other sectors
With the new testo 860i, Testo presents an innovative, wireless thermal imager for smartphones that has been specially developed for fast and precise spot checks. The testo 860i is the ideal solution for heating, air conditioning and refrigeration technicians, maintenance and building services specialists and for numerous other areas of application. Thanks to its ease of use, razor-sharp thermal images and seamless integration into the testo Smart App, it offers high efficiency and flexibility in the thermal inspection of technical systems, components and building features such as windows, doors and walls.
Fast and precise measurements for a wide range of applications


Fast and precise measurements for a wide range of applications
With the testo 860i, temperature differences (Delta T), heat sources (hotspots) and humidity can be determined quickly and reliably directly in the thermal image. Together with the testo Smart App, the imager offers a wide range of practical measurement programs that make everyday work much easier:
- DeltaHeat: Enables quick determination of the temperature spread of flow and return temperatures on radiators and provides optimization tips.
- DeltaCool: Determines the differential temperature on refrigeration and air conditioning systems step by step.
- Thermography: Quickly detects hotspots and heat development – ideal for preventive maintenance of electrical and mechanical systems and for identifying hidden defects such as leaks in underfloor heating systems.
- Humidity mode: Visualizes damp spots on walls, ceilings and corners and enables simple assessment of the risk of mould using a traffic light scale (in conjunction with the testo 605i thermo-hygrometer).
These functions allow rapid diagnosis of problems that would otherwise remain undetected and could potentially lead to costly or dangerous follow-on damage.
Easy handling and flexible use
The testo 860i not only impresses with its high functionality, but also with its exceptional user-friendliness. Thanks to the retractable clip, the imager can be attached directly to the smartphone or tablet, allowing easy one-handed operation. The wireless connection to the testo Smart App allows the imager to be used with both hands. The App offers an intuitive user interface, guided measurement programs, easy export of thermal images and fast documentation – including sending reports by email.


Robust, durable and made for though everyday use
The testo 860i impresses with its high durability: With a protection class of IP54, drop resistance from a height of up to 1.5 meters and a rechargeable lithium-ion battery with USB-C connection, the imager offers a long service life and is perfect for demanding everyday working life.
The testo 860i wireless thermal imager for smartphones is also available as a kit with a practical case, and is now available.