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    testo 420 - Air Flow Hood 

    0563 4200
    $5 277.00 $5 804.70
    1
  1. 16 measurement points that records Temperature, Humidity, Differential & Absolute Pressure. 
  2. Highly precise readings at swirl outlets thanks to flow straightener. 
  3. IOS & Andriod App Integration via Bluetooth connectivity. 
  4. Onsite report generation & email. 
  5. The Testo 420 volume flow hood is suited for HVAC systems and comes with a control panel for displaying measurement data. The control panel can be tilted or removed to suit user requirement. 
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      testo Smart App

      The App for all applications. Multifunctional. Continuously up to date. Free.

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      Air balancing – time saving up to 30%

      New PRO measuring program in the testo Smart App

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      Volume flow hood weighing less than 2.9 kg

    The Testo 420 measuring instrument enables you to measure flow velocity, volume flow, absolute pressure, temperature and relative humidity. The automatic zeroing function ensures higher accuracy for low pressures.

    All measuring values are easy to read on the large display which has an illumination function. For analysis and documentation, measurement data can be saved and measurement protocols can be created directly on site using the testo 420 App. In addition the measurement data can be easily accessed via PC without any additional software thanks to the plug & play function.

    The Testo 420 volume flow hood with its integrated measuring instrument was not only developed to measure volume flow measurement. The measuring instrument can also be taken off the hood and used to measure pressure, flow and volume flow measurements in a duct. Simply attach a Pitot tube and connection hoses (both optional). With integrated, timed and multi-point mean calculation.

    High measuring accuracy at swirl outlets thanks to volume flow straightener

    Volume air flow is frequently measured at swirl outlets. Air flows are often incorrectly measured due to the turbulent air at these outlets.

    The Testo 420 enables you to significantly reduce these measurement errors. The integrated volume flow straightener calms the turbulence and converts it into a virtually uniform air flow. This enables accurate calculation of volume flow in the 80 to 3,500 m3/h range.

    Create protocols directly on site and E mail them using the Testo 420 App

    Take advantage of further practical functions and download our free App. Because the App connection enables mobile devices such as smartphones and tablets to be used as a secondary display and as a remote control via Bluetooth.

    The App enables live measurement on HVAC systems using a start and stop function and the saving of measurement data in txt format. You can create the measurement protocol directly on site using the App. Measurement results, such as the overall volume flow and the air exchange rate, can be directly assigned to customer-specific protocol templates. You can then send your readings and protocols via the e-mail function. This means you save a considerable amount of time and increase efficiency. 

    testo 420 volume flow hood including measuring instrument, 610 x 610 mm hood, 5 x tension rods, USB cable, batteries, trolley and protocol certificate.

    Temperature - NTC

    Measuring range
    -20 to +60 °C
    Accuracy
    ±0.8 °C (-20 to +0 °C)
    ±0.5 °C (0 to +60 °C)
    Resolution
    0.1 °C
    Reaction time
    45 s (t₉₀)

    Humidity - Capacitive

    Measuring range
    0 to 100 %RH
    Accuracy
    ±1.0 %rF/year Drift
    ±0.03 %RH/K (at 0 to 60 °C )
    ±1.0 %rF Hysterese
    ±1.8 %RH +3 % of mv (at 25 °C, 5 % to 80 %RH)
    Resolution
    0.1 %RH

    Differential Pressure - Piezoresistive

    Measuring range
    -120 to +120 Pa
    Accuracy
    ±2 % of mv + 0.5 Pa at +22 °C, 1013 hPa
    Resolution
    0.001 Pa
    Reaction time
    1 s (t₉₀)

    Accessories

  6. Accessories
    Replacement Hood 360mm, 360mm
    Replacement hood (360 x 360 mm) for testo 420
      :
      0554 4200
      $459.00 $504.90
      1
    • Accessories
      Replacement Hood 305mm, 1220mm
      Replacement hood (305 x 1220 mm) for testo 420
        :
        0554 4201
        $530.00 $583.00
        1
      • Accessories
        Replacement Hood 610mm, 1220mm
        Replacement hood (610 x 1220 mm) for testo 420
          :
          0554 4202
          $530.00 $583.00
          1
        • Accessories
          Tripod for testo 420
          Extendable tripod (up to 3.3 m) with wheels
            :
            0554 4209
            $868.00 $954.80
            1
          • Additional accessories and Spare parts

          • Additional accessories and Spare parts
            Connection hose, silicone
            Connection hose, silicone - max. load capacity up to 700 hPa (mbar)
              :
              0554 0440
              $101.00 $111.10
              1
            • Additional accessories and Spare parts
              Connection hose
              Connection hose silicone-free for differential pressure measurement, length 5 m, load up to maximum 700 hPa, (mbar)
                :
                0554 0453
                $101.00 $111.10
                1
              • Additional accessories and Spare parts
                Staurohr
                Stainless steel Pitot tube, length 500 mm, Ø 7 mm - for measuring flow velocity
                  :
                  0635 2045
                  $303.00 $333.30
                  1
                • Additional accessories and Spare parts
                  Staurohr
                  Stainless steel Pitot tube, length 350 mm, Ø 7 mm - for measuring flow velocity
                    :
                    0635 2145
                    $268.00 $294.80
                    1
                  • Additional accessories and Spare parts
                    Staurohr
                    Stainless steel Pitot tube, length 1000 mm, Ø 7 mm - for measuring flow velocity
                      :
                      0635 2345
                      $753.00 $828.30
                      1