Funding programme for improved indoor climate in classrooms

Throughout the coronavirus pandemic, a tranche of measures have been aimed at minimising the risk of infection. “Hands. Face. Space.” (washing hands, wearing a mask in everyday life and social distancing) are key pillars for preventing the potential transmission of viruses. Ventilation too.

The spotlight has now fallen on the risk of infection in schools, especially in full classrooms. Lively discussions are now taking place about air filtration, as well as increasingly about the requisite air exchange in classrooms through the use of appropriate school ventilation systems. A healthy indoor climate is about more than just ensuring virus-free air. The oxygen or CO2 concentration and air humidity need to be monitored.

There is a massive need to install adequate room ventilation systems in school buildings to provide good indoor air conditions. This can only be provided by systems designed to refurbish existing schools.

Take advantage of the funding programme recently passed by the German Federal Office of Economics and Export Control (BAFA) for the installation of new stationary air handling units into facilities for children under the age of 12. More about this below.

What is the current situation in school buildings?

Centralised ventilation units are now integral components of the building specifications for new schools. However, centralised air handling units are hardly ever installed in existing buildings. The incursion into the existing building structure would be too complex and expensive. And yet, decentralised ventilation units provide solutions that are in no way inferior to centralised ventilation technology. The major benefit of decentralised units like the Kampmann WZA: the structural work involved is many times lower.

What are the structural benefits of using a decentralised unit?

A separate decentralised school ventilation unit is installed in each and every classroom. There is minimal disruption to the normal running of the school as the structural work is only done on the respective classroom and independently of the heating system already installed. Generally only one core opening is required if the decentralised ventilation unit is installed as a wall-mounted unit. Alternatively, a fan light on the window can be replaced. This work, including drilling through the wall and commissioning, is done by a specialist contractor.

New decentralised WZA ventilation unit

The major benefit of the new Kampmann product is its “plug-in” capability. No electrician is needed for the installation of the compact school ventilation unit and it is ready to use as soon as it has been set up. All air deflections with shut-off dampers are factory-wired. This is a key difference from many other models on the market. The external dimensions of the unit – 150 (W) x 66 (D) x 210 (H) cm – are minimal, ensuring that the unit can be positioned in the room as required. The range includes various colours, enabling the unit to be individually adapted to the respective interior design. A CO2 sensor and appropriate configuration of the air volumes guarantee compliance with the usual standards and comfortable operation.

Safety is a priority here: the school ventilation unit can also be connected to any fire alarm system already installed.
The unit weighs a total of 400 kg and is constructed in two sections with a lower heat recovery component and an upper operational component containing all the electrical components and outside air filter. The “two-section” design of the unit ensures that it is simple to deliver and install along with the casing also supplied.


Operation and ongoing running of the unit

The decentralised WZA ventilation unit features four stages plus standby, which can be scrolled through using a single colour-coded button:


  • Unit is off
  • When the CO2 content in the classroom exceeds 600 ppm, the unit automatically switches to automatic ventilation

White - Automatic ventilation

  • For everyday operation
  • Automatic and continuously variable control of the air volume according to the CO2 content in the classroom
  • Unit automatically switches to standby if the CO2 content is below 500 ppm for a minimum of 2 hours and hence a good air quality has been restored

Blue - Purge ventilation

  • The unit delivers full air output (over 1,000 m³/h) for 10 minutes, and then switches automatically to automatic ventilation
  • This corresponds to a purge or shock ventilation function and can be used in breaks or in the event of a pandemic or flu infection
  • No comparable product on the market offers this high air output

Magenta - Continuous ventilation

  • The unit permanently delivers an air volume of 800 m³/h for 8 hours independently of the demand for ventilation based on the CO2 content in the classroom
  • This function aids infection prevention, as is needed during a pandemic or flu epidemic to ensure that there is always an adequate air exchange
  • At the end of 8 hours, the unit automatically switches back to automatic ventilation

Turquoise - Quiet ventilation

  • Reduced operation at a low level
  • Suitable for use in exam situations, among other things

The unit’s one-button operation enables users to operate the unit intuitively and simply. All operating times and parameters can be subsequently parametrised online if customised adjustments are needed for specific usage situations. A key feature of the school ventilation unit is its lower sound level, thanks to the sophisticated insulation dampers in the basic unit and housing. They guarantee the quiet operation of the unit.

A nominal minimal volumetric flow of 25 m³ per person per hour is specified, but a minimum of 30 m³ is recommended to be eligible for funding for the new installation of a stationary air handling unit. The WZA exceeds these requirements.

Continuous ventilation mode supplies 800 m³/h.

750 m³/h would be needed in nominal air mode with 30 pupils: 30 x 25 m³/h = 750 m³/h
In purge ventilation operating mode, the unit achieves an air output of 1,000 m³ and is therefore above the required air volume: 30 x 30 m³/h = 900 m³/h.
Of course, these values would also be achieved when self-regulated in automatic mode when requested by the CO2 sensor.

Ease of maintenance

The design of the decentralised WZA ventilation unit is fit-for-purpose and so provides for ease of maintenance. This can be done in most cases by trained caretakers, who can simply read off the respective error messages. As a result, no specialist trade persons need to be called in.

The design of the upper part of the unit is well thought out. The fan can simply be pulled out on a “drawer” for maintenance purposes. The outside air filter is also easily accessible and can thus be replaced with ease.

Seamless operation is ensured in normal conditions and operation as low as outside temperatures of -10°C, in part thanks to the installation of a frost-proof enthalpiy heat exchanger. There is no need to connect the unit to a sewage system, as no condensate is produced in the unit. And there is also no need for a condensate pump.

A further key aspect has been taken into account for the use of this unit in schools: the casing. It is accident-proof, robust and therefore minimally susceptible to vandalism.

No drying out of mucous membranes, thanks to the enthalpiy heat exchanger 

The enthalpiy heat exchanger fitted in the school ventilation unit ensures that a large proportion of the room air humidity and heat and/or cold from the extract air/exhaust air can be recovered. This avoids energy losses and reduced air humidity, with the associated environmental and economic benefits. However, of crucial importance are the health aspects for the people who spend time in the room. Particularly in winter, rooms are often not sufficiently humid due to the hot air from the heating system. This results in dry mucous membranes, which have been proven to promote the occurrence of infections. These quality features are what decisively distinguish the Kampmann unit from other decentralised ventilation units on the market.

Other solutions for optimum room air in classrooms and school buildings 

Kampmann has been supplying the KA-520 air purifier since the middle of 2020. It is an ideal solution for closed rooms without centralised or decentralised ventilation systems. The KA-520 is a portable plug & play upright unit with an extremely large filter surface. Thanks to its H14 HEPA filters, 99.995 % of all viruses and germs are filtered out of the air. The KA-520 XL Pro or the KA-520 XXL, which are capable of purifying up to 720 m³/h or 1,340 m³/h ambient air with low noise levels are especially suitable for schools and public facilities.
You have our subsidiary NOVA Apparate, part of the Kampmann Group, as a strong partner at your side for centralised ventilation systems.
Are you currently planning a school ventilation system for an existing building? Simply get in touch with us. We would be delighted to develop a scheme and provide you with a quotation.

What's the next step?

The most important factor for you is to have a strong advisory partner at your side. I look forward to your call or e-mail enquiry about decentralised school ventilation.

I would be delighted to explain our WZA in detail to you and answer any questions you may have.


Frank Heidrich

+49 591 7108-115