OVERVIEW & SPECIFICATION

The testo 420 air capture hood for larger air inlets and outlets enables fast and precise compliance with hygiene guidelines and requirements concerning room air quality. It provides reliable support with the calculation of the overall air capture on HVAC systems, for instance in hospitals, office buildings or commercial buildings.
High measuring accuracy at swirl outlets thanks to air capture straightener
Air capture is frequently measured at swirl outlets. Air flows are often incorrectly measured due to the turbulent air at these outlets.

Temperature – NTC
Measuring range	-20 to +70 °C
Accuracy	±0.5 °C (0 to +70 °C) ±0.8 °C (-20 to +0 °C)
Resolution	0.1 °C
Reaction time	45 s (t90)

Humidity – Capacitive
Measuring range	0 to 100 %RH
Accuracy	±1.8 %RH + 3 % of mv at +25 °C (5 to 80 %RH)
Resolution	0.1 %RH

Humidity – Capacitive

Measuring range

0 to 100 %RH

Accuracy

±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)

Absolute Pressure
Measuring range	700 to 1100 hPa
Accuracy	±3 hPa
Resolution	0.1 hPa
Reaction time	1 s

Volume flow
Measuring range	40 to 4000 m³/h
Accuracy	±3 % of mv + 12 m³/h at +22 °C 1013 hPa (85 to 3500 m³/h)
Reaction time	1 s (t90)
Resolution	1 m³/h

General technical data
Dimensions	610 x 610 mm (Standard hood)
Operating temperature	-5 to +50 °C
EU-/EG-guidelines	EU-guideline 2014/30/EU
Warranty	2 years
Battery type	Alkali manganese, mignon, type AA
Battery life	40 h
Display size	3.5″
Display function	Dot matrix
Display ligthing	with illumination
Interface	Micro-USB; Bluetooth® 4.0 wireless technology
Memory	2 GB (internal)
Storage temperature	-20 to +60 °C
Weight	2900 g

testo-420