Hot wire probe (digital) - with Bluetooth® including temperature and humidity sensor

Order-Nr.  0635 1571

  • Intuitive: clearly structured measurement menu for volume flow and parallel determination of air velocity, volume flow, air temperature and humidity

  • Precise: accurate measurement results from 0 to +50 m/s and automatic absolute pressure compensation

  • Convenient: Bluetooth connection between measuring instrument and probe, with a practical button on the handle for storing individual readings, convenient measurement in any cross-section with scaled telescope (up to 1 m), optionally extendable to 2.0 m

  • Intelligent calibration concept

For measurements in ventilation ducts: use the hot wire probe (with the compatible measuring instrument) to measure air velocity, volume flow, air temperature and humidity. The readings are transmitted directly to your measuring instrument via Bluetooth, making your measurements particularly convenient.


Product Description

Use the hot wire probe with the compatible testo multifunction measuring instrument (please order separately) to determine air velocity, volume flow, air temperature and humidity.


Hot wire probe with Bluetooth including temperature and humidity sensor – features

The readings of the hot wire probe are transmitted to your measuring instrument via Bluetooth, up to a distance of 20 m.

The hot wire probe is equipped with a telescope, which can be extended to a maximum length of 1.0 m. The immersion depth is easy to read, even if visibility is poor, thanks to the high-contrast scaling.

The clearly structured measurement menu for volume flow enables the measuring instrument to be operated intuitively. The volume flow is precisely calculated thanks to convenient input of the size and geometry of the duct cross-section. Timed and multi-point mean calculation, average volume flow, current reading and min./max. values are displayed in the measuring instrument.

Particularly useful: press the button on the hot wire probe to operate the measuring instrument. For example, to store individual readings for multi-point mean calculation or to start and stop measurement series for mean calculation over time.

Integrated sensor protection: when you are not using the hot wire probe, the rotatable protective cap protects the air velocity sensor from mechanical stress.


Wireless and space-saving: more applications, less equipment

Endlessly versatile: a universal handle can be connected to all probe heads – so you can master more applications using less equipment and save space. The Bluetooth handle makes it more convenient to carry out your measurement and guarantees less cable clutter in the case.

Or order the cable handle to connect testo probe heads. This is an advantage if Bluetooth signals are not permitted. If the sensors (air velocity, temperature, humidity) need to be replaced in the distant future, you can change the probe head.

If required, you can also fit the hot wire probe with the telescope extension (available to order separately). You can therefore attain a total length of 2 metres, making it easy to carry out measurements on large ventilation systems.


Intelligent calibration concept

You will get exceptionally accurate measurement results with the digital probe, because the measuring instrument makes measurement uncertainty a thing of the past. You only need to send the probe head in for calibration – so the measuring instrument remains in continuous use.


Areas of application for the hot wire probe with Bluetooth

Ventilation ducts: Use the hot wire probe to measure air velocity, air temperature and humidity in ventilation ducts with reliability.
Since the measuring range goes up to +50 m/s and the total length of the probe can be extended to 2.0 m (please order the telescope extension separately), measurements can even be carried out on large ventilation systems.


Delivery Scope

Hot wire probe with Bluetooth including temperature and humidity sensor (consisting of hot wire probe head, handle adapter and Bluetooth handle), 4 x AA batteries, telescope (extendable to 1.0 m) and calibration protocol.

Related products

Technical Data

Temperature - NTC

Measuring range

-20 to +70 °C


±0.5 °C (0 to +70 °C)

±0.8 °C (-20 to 0 °C)


0.1 °C

Humidity - Capacitive

Measuring range

5 to 95 %RH


±3 %RH (10 to 35 %RH)

±2 %RH (35 to 65 %RH)

±3 %RH (65 to 90 %RH)

±5 %RH (Remaining Range)

±0.06 %RH/K (k=1)

long-term stability: ±1 %RH / year

Hysteresis: ±1.0 %RH


0.1 %RH

Absolute Pressure

Measuring range

+700 to +1100 hPa


±3.0 hPa


0.1 hPa

Velocity - Hot wire

Measuring range

0 to 50 m/s


±(0.03 m/s + 4 % of mv)

(0 to 20 m/s)

±(0.5 m/s + 5 % of mv)

(20.01 to 30 m/s)


0.01 m/s

General technical data

Storage temperature

-20 to +60 °C


400 g


780 x 50 x 40 mm

Operating temperature

-5 to +50 °C

Length telescope

1,000 mm

Probe head diameter

9 mm

Diameter telescope

16 mm

Product colour


Diameter probe shaft

9 mm

Length probe shaft

230 mm

Battery life

21.5 h

Battery type

4 x type AA batteries

Data transfer


Radio range

20 m


Sensor heads