Ventilation and air conditioning systems

Balanced ventilation system (BVS)

Increasingly well insulated buildings with increasingly well sealed shells lead to humidity and odours no longer being able to permeate through the joints. Added to this is the fact that fresh air can also not enter the house unhindered. This is where a balanced ventilation system (BVS) comes in: These ventilation-supported systems ensure an air exchange by introducing fresh air into the rooms and transporting used air, pollutants and odours away. This increases well-being and prevents moisture damage and mould:

Indoor ventilation maintenance – here’s how it’s done

Indoor climate measuring instruments and probes from Testo support you in all phases of a BVS: From the planning phase through the optimum adjustment up to regular monitoring of the performance – intuitively, precisely and taking legal conformity into consideration. Indoor climate measurement technology from Testo can of course be used not only for centralized, but also for decentralized indoor ventilation.


testo 440

Determining volume flow and air quantity in a ventilation duct

With the testo 440 and the suitable hot-wire or vane probe, you determine volume flow in a duct quickly and precisely.

  • Guarantee room load removal

  • Ensure efficient operation

  • Save measurement data and export for commissioning report

testo 440 100 mm Vane Kit

to the kit

Testing air exchange rate at vents

With the testo 440, a vane probe (Ø 100 mm) and the corresponding testovent 417 flow straightener set, you determine the volume flow at supply or output air vents simply and without error.

  • Guarantee room load removalgewährleisten

  • Ensure sufficient fresh air supply and ventilation

  • Avoid draughts and noise formation

testo 440 CO2 Kit

to the kit

Measuring humidity and temperature in rooms

You record the air humidity and the air temperature in rooms in no time using the testo 440 and the suitable humidity/temperature probe.

  • Ensure a healthy indoor climate

  • Avoid mould damage

  • Protect building substance

Adjusting balanced ventilation systems (BVS) – with Testo technology

Choose your application

Ventilation and air conditioning systems

Ventilation and air conditioning systems consume a lot of energy. However, they are indispensable for a pleasant room climate. Measuring instruments from Testo help you to control the systems efficiently in order to quickly achieve significant savings and ensure a comfortable climate in all rooms.

For flow measurement in the duct and at the outlet, Testo offers you various measurement solutions - from small Testo Smart Probes to digital anemometers to multifunctional climate measuring instruments.

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testo Smart App

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The testo Smart App guides you quickly and easily through measurements on refrigeration, air conditioning and heating systems.

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Compatible with all Bluetooth-enabled Testo measuring instruments


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PRO measuring programs

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Customer services

In case of malfunctions, send in your meter with a short description of the error. Please also include your telephone number for any queries. Normally you will receive your meter back within one week.


Our subsidiary Testo Industrial Services supports you every day in ensuring quality while always complying with the relevant standards and guidelines. You get all the services you need for this from a single source.

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