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Testo 435-1

Multi-Function HVAC and IAQ Meter

Brand: Testo
Model No: 435-1
MPN: 0560 4351
Our Model No: 4351
Condition: NEW
PDF Document Icon Data Sheet (1.75 MB)
Sale $512.55
Add to Cart

Product Features:

  • Ideal for spot check measurements
  • Compatible with wide variety of probes to measure and record airflow, temperature, and indoor air quality readings
  • May be used with wireless temperature probes for remote measurement
  • Easy operation with selectable user profiles and probe specific menus
  • Backlit LCD for easy viewing
  • Measurement values may be printed cyclically on a Testo fast printer (optional, available separately)
  • IP54 Protection class

The Testo 435-1 Multi-Function HVAC and IAQ Meter allows you to carry out the measurements that are necessary to check and adjust the airflow of air conditioning systems, and to also assess the quality of indoor air. With the 435-1, you can also easily pinpoint and troubleshoot airflow problems with HVAC systems, immediately seeing the results of corrections. Commissioning, validating, benchmarking, or simply adjusting HVAC systems are all easy with the 435-1 meter.

The 435-1 Multi-Function Meter accepts a wide variety of probes to measure and record airflow, temperature, and indoor air quality readings. Probe dependent menus and selectable user profiles ensure that the 435-1 meter is always ready to use. Easy setup of user-defined IAQ and airflow/duct profiles allow for fast measurement of many different tasks, and with a range of probe choices available, the testo 435-1 is ready to handle a vast array of indoor air quality applications.


Flow Measurement in Ventilation Ducts Using a Thermal Anemometer and Vane Anemometer

The Testo 435-1 Multi-Function HVAC and IAQ Meter is compatible with compact anemometer probes and pitot tubes for measuring the flow and volumetric flow in a ventilation duct. Selecting a suitable probe or measuring instrument depends on the flow velocity in the ventilation duct. This can be broken down into three sub-ranges: low flow velocities (0 to 5 m/s), medium flow velocities (5 to 40 m/s), high flow velocities: 40, 70, 100 m/s.

The flow sensors for duct measurement are all equipped with telescopes making them easy to use in large air ducts. Air temperature and humidity can also be measured with the same probe as the flow velocity if required. According to the required application, choose between a thermal probe, vane probe or pitot tube for measuring the flow measurement in the duct.

Measurement at the Air Outlet

Every duct inlet and outlet should only contain the volumetric flow that according to calculations is a basic prerequisite to an efficient functional system.

Large vane anemometers with 100 mm diameters are suitable for measuring the volumetric flows at duct outlets (order no. 0635 9435), as it integrates the flow velocity over a larger area, thereby determining disturbance from the air grille (loop method).

To measure the suction or blowing vents of air grilles and poppet valves, a volumetric flow rate funnel set is ideal (order no. 0563 4170), as is the large 100 mm vane anemometer (order no. 0635 9435). The entire volumetric flow is recorded with the aid of the funnel without the need for conversion on the basis of the flow velocity and area. This method of flow measurement is simple and reliable.

Measurement of the Air and Surface Temperature

For people to be comfortable and perform at their best, it is crucial that the rooms they occupy are correctly air conditioned. As well as the structural conditions and personal perception, the following factors also contribute significantly to the existence of a pleasant indoor climate: the indoor air and surface temperature of walls, windows, floors and ceilings.

There is a range of optional temperature probes available for the 435-1 Multi-Function HVAC/IAQ Meter. Temperature probes with a sprung cross-band sensor element for measurement on surfaces are an ideal option. The sprung cross-band sensor element fits on any surface, taking the actual temperature of the measured object in just a few seconds (for example the fast-reaction surface probe, order no. 0602 0393).

In order to allow a fast measurement of air temperature, the temperature sensor is free in Testo's air probes (e.g. NTC probe 0613 1712). Immersion/penetration probes can also be used for measurements in air. However, the response time is then about 40 to 60 times higher than the indicated value which was measured in water.

Measurement of Radiated Heat

The 435-1 Multi-Function HVAC/IAQ Meter is your reliable aid to measuring thermal comfort. The optional, attachable globe thermometer (order no. 0602 0743) enables measurement of radiated heat (that is, the operative or perceived temperature). The operative temperature measured with a Globe thermometer with a 150 mm diameter preferably corresponds with people's perceived temperature to +/- 0.41 K.

The temperature measurements in a room (air temperature and operative temperature) are to be taken in the same place and same general conditions as the measurement of indoor air velocities.

Measurement of Indoor Air Quality (CO2)

Bad indoor air quality due to high concentrations of CO2 can cause tiredness, lack of concentration and even illness. Therefore, to ensure sufficient indoor air quality, the CO2 concentration should generally not exceed 1000 ppm. Values of 700 to 1500 ppm can be viewed as the "reference range".

The IAQ probe (order no. 0632 1535) is particularly suitable for monitoring indoor air quality controls. This probe can be used to record CO2, temperature and relative humidity at the same time.

CO Measurement

Carbon monoxide (CO) is an odorless, invisible and tasteless gas, but also poisonous. It is produced during the incomplete combustion of substances containing carbon, such as coal, wood, oil, natural gas, etc., in heat sources and combustion engines. The CO concentration will increase quickly, particularly if there is not enough oxygen available. This may have adverse effects on health.

The ambient CO probe (order no. 0632 1235) and Testo 435-1 Multi-Function HVAC/IAQ Meter are able to detect even the smallest quantities of CO in ambient air.

  • 1 - IAQ/HVAC Multifunction Meter (435-1)
  • 2 - AA Batteries
  • 1 - Calibration Protocol
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Air Probes
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0602 1793 Testo 0602 1793 Robust Air Probe, Thermocouple Type K Add to Cart
Sale $58.65
0613 1712 Testo 0613 1712 Robust Air Probe with mini-DIN Connection, NTC Add to Cart
Sale $72.25
CO Probes
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0632 1235 Testo 0632 1235 Handheld External Carbon Monoxide Probe Add to Cart
Sale $462.40
Comfort Probes
Model Description Buy Now Price
0602 0743 Testo 0602 0743 Globe Probe with 6-in. Diameter, Type K Thermocouple Add to Cart
Sale $460.70
0632 1535 Testo 0632 1535 IAQ Probe for CO2, Humidity, Temperature, and Absolute Pressure Add to Cart
Sale $838.10
Immersion and Penetration Probes
Model Description Buy Now Price
0602 1293 Testo 0602 1293 Waterproof Immersion/Penetration Probe, Type K Thermocouple Add to Cart
Sale $43.35
Pressure Probes
Model Description Buy Now Price
0638 1835 Testo 0638 1835 Absolute Pressure Probe with Cable, 29 psi (2000 hPa) Add to Cart
Sale $411.40
Surface Probes
Model Description Buy Now Price
0602 0394 Testo 0602 0394 Surface Measurement Probe Head, Type K Thermocouple Add to Cart
Sale $67.15
0602 0393 Testo 0602 0393 Surface Probe with Sprung Thermocouple Strip, Type K Add to Cart
Sale $127.50
0602 4592 Testo 0602 4592 Pipe Clamp Probe, Max. 2.5 in. Diameter, Type K Thermocouple Add to Cart
Sale $135.15
0602 4692 Testo 0602 4692 Pipe Clamp Probe, Max. 1 in. Diameter, Type K Thermocouple Add to Cart
Sale $67.15
Velocity Probes
Model Description Buy Now Price
0635 1025 Testo 0635 1025 Telescopic Hot-Wire Probe for Velocity and Temperature, NTC Add to Cart
Sale $311.10
0635 1535 Testo 0635 1535 Thermal Velocity Probe with Built-In Temperature and Humidity Sensors Add to Cart
Sale $562.70
0635 9335 Testo 0635 9335 Telescopic Vane Probe for Duct Exits, 2.36 in. (60 mm) Diameter Add to Cart
Sale $499.80
0635 9435 Testo 0635 9435 Vane Probe for Testovent Funnels, 3.9 in. (100 mm) Diameter Add to Cart
Sale $374.85
0635 9535 Testo 0635 9535 Telescopic Vane Probe for Ducts, 0.6 in. (16 mm) Diameter Add to Cart
Sale $499.80
Data Sheet: PDF Document Icon (1.75 MB)
Manual: PDF Document Icon (974 KB)
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