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Hot wire probe (digital) - including temperature and humidity sensor, wired

Hot wire probe (digital) including temperature and humidity sensor, wired
Hot wire probe (digital) including temperature and humidity sensor, wired
Hot wire probe (digital) including temperature and humidity sensor, wired
Hot wire probe with scaled telescope
Volumetric flow measurement in ventilation ducts with hot wire probe and testo 440
Volumetric flow measurement in ventilation ducts with hot wire probe and testo 440
The wired digital hot wire probe offers precise, all-in-one measurement of air velocity, volume flow, temperature, and humidity in ventilation systems. With a telescopic shaft, intuitive controls, and smart calibration, it’s built for reliable HVAC assessments in demanding environments.
  • Comprehensive HVAC Measurement – Simultaneous detection of air velocity, volume flow, air temperature, and humidity for efficient ventilation assessments.
  • High Precision Performance – Accurate results from 0 to +30 m/s with automatic absolute pressure compensation for reliable data in any condition.
  • Optimised for Accessibility – Scaled telescope extends up to 1.0 m (optionally to 2.0 m), enabling comfortable measurements even in large or hard-to-reach ducts.
  • Intelligent Calibration Concept - Calibration is handled via the probe itself, allowing continuous use of the measuring instrument and minimising disruption.
The digital hot wire probe with integrated temperature and humidity sensors is the ideal solution for accurate and convenient airflow measurement in ventilation ducts. Designed for use with a compatible testo multifunction measuring instrument (sold separately), this robust wired probe measures air velocity (0 to +30 m/s), volume flow, temperature, and humidity with high precision.

A scaled telescope extends up to 1.0 meter and is optionally extendable to 2.0 meters, allowing easy access to deep or high-up ductwork. Thanks to absolute pressure compensation, the probe ensures consistent accuracy under changing environmental conditions.

A built-in button on the handle lets you store readings and manage measurement series directly at the measurement point, simplifying the workflow. The rotatable sensor protection cap helps preserve the sensitive hot wire sensor from damage and debris during transport or storage.

The probe is part of a modular system featuring a universal handle – connect various probe heads to reduce gear load and increase testing flexibility. Users can switch to a Bluetooth® handle (optional) for wireless operation or extend the reach with a telescopic extension for measurements in large-scale systems.

With Testo’s intelligent calibration concept, only the probe head requires calibration, ensuring minimal downtime and continued measuring efficiency.

Temperature - NTC

Measuring range
-20 to +70 °C
Accuracy
±0.8 °C (-20 to 0 °C)
±0.5 °C (0 to +70 °C)
Resolution
0.1 °C

Humidity - Capacitive

Measuring range
5 to 95 %RH
Accuracy
Hysteresis: ±1.0 %RH
long-term stability: ±1 %RH / year
±3 %RH (10 to 35 %RH)
±0.06 %RH/K (k=1)
±3 %RH (65 to 90 %RH)
±2 %RH (35 to 65 %RH)
±5 (Remaining Range)
Resolution
0.1 %RH

Absolute Pressure

Measuring range
+700 to +1100 hPa
Accuracy
±3.0 hPa
Resolution
0.1 hPa
Hot wire probe including temperature and humidity sensor (consisting of hot wire probe head, handle adapter and cable handle (cable length 1.4 m)), telescope (extendable to 1.0 m) and calibration protocol.

Accessories

Sensor heads

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Testo Ltd
Newman Lane
GU34 2URAlton
HampshireUnited Kingdom
01420 544433

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