Innovation - The Eco-Fan Made in Germany

The Eco-Fan ensures high indoor air quality.

The Eco-Fan constantly introduces fresh air into indoor spaces, protecting against bacteria, viruses, pollen, dust, and filtering aerosols. Furthermore, the Eco-Fan maintains the carbon dioxide concentration level of 1,000 ppm CO2 as recommended by the Ventilation Working Group.

The effect: People in the rooms are much more focused, productive, and feel comfortable – beneficial in classrooms, seminar rooms, offices, labs, as well as in daycare centers, hospitals, residential homes, and other private and commercial spaces.

The Eco-Fan 9038 is a decentralized (local), retrofitable ventilation system with a regenerative magnetically supported and rotating counterflow heat exchanger. The fan is preferably installed in an insulating glass pane (double glazing) or with a sandwich panel in the facade.

In addition to dry heat recovery (HRV), the Eco-Fan also offers the option of moisture recovery (ERV). The degree of HRV is up to 90%. This means that the existing room temperature is nearly maintained through the constant inflow of fresh air. Only a small amount of additional heat is required to maintain the desired comfort temperature.

In summary, the Eco-Fan is a regenerative heat exchanger for gaseous media (air) for facility ventilation.

The installation should be done by a glazier. The glass surface must be at least 500 x 500 mm in size, a cutout of 371 mm is required, and the glass thickness should be less than 6.5 mm.

In the case of new construction or special glass production, the opening can also be made directly by the glass manufacturer. A standard glass pane is then sealed with the direct perforation of 371 mm by the manufacturer and ordered with the respective gas filling. The installable support ring has a diameter of 368 mm and can be easily inserted into the pre-drilled hole. The subsequent installation can then be done in a very short time (see attached installation manual).

The Eco-Fan 9038 is largely transparent in construction and has an outer diameter of 384 mm. The heat exchanger drum extends 200 mm from the pane into the room. The total depth is 297 mm and the total weight is 8 kg.

The Eco-Fan exchanges indoor air for fresh air through two insulated fans. The rotating drum absorbs the heat from the outgoing air stream and transfers it to the incoming fresh air.

A net-like fleece, wrapped multiple times around the drum, absorbs the heat from the outgoing air and transfers it to the incoming fresh air.

The polyethylene (PE) fleece has the property of storing heat particularly well and corresponds to filter class "G4ac" according to EN779:2012 and belongs to the category of fine dust filters for particles 1 – 10 µm.

Sie haben hohe Ansprüche an Ihre Gesundheit und die Umwelt?

Do you have high standards for your health and the environment?

Then you should choose only the best for yourself, your family and employees, your guests and clients, your students, patients, and residents.

      • Eco1 = ecological; the Eco-Fan conserves fossil resources to the highest degree. 
      • Eco2 = economical: through heat recovery, you save significantly on ongoing energy costs. 
      • Eco3ecotrophological: Air is a food. Viruses and other pests contaminate the household.

        The Eco-Fan ensures a constant supply of fresh air in the room and expels viruses, bacteria, and dust to the outside while filtering aerosols.


The fan with the three eco's

Up to 90% of the heat is recovered


Decentrally controlled and easy to retrofit


Helps regulate room humidity



For a better environment

It is irrelevant whether we believe that there is no climate change, whether we are convinced that climate change is coming, or whether we are certain that climate change is already here. One thing unites us all; we all agree that the excessive consumption of fossil fuels is not beneficial for the planet Earth.

Of course, we can think that all countries on this Earth should switch to renewable or alternative energies simultaneously and immediately. However, we also know that this will not happen.

There is only one alternative, that each individual can do something for themselves – otherwise, it will not be possible. With the Eco-Fan, we make a significant contribution to a better environment.


The Eco-Fan conserves fossil resources.

Fossil fuels such as oil, gas, and coal are not infinitely available on this Earth; they are limited. With the Eco-Fan, we significantly reduce the consumption of these fuels.

Energy Costs

The Eco-Fan saves energy costs.

Fossil fuels, either directly converted into heat or used as energy to generate electricity, are becoming scarcer and therefore more expensive due to their limited availability and global political conditions.

With the Eco-Fan, much less incoming heat is required. Energy costs are reduced directly and noticeably.


The Eco-Fan promotes our health and performance.

Health is not everything – but without health, everything is nothing!

We live in a world where the performance of each individual is of great importance for the well-being of all. If we are not healthy and capable ourselves, we harm ourselves primarily, but also our families and the community. The Eco-Fan provides a healthy indoor climate and thus significantly contributes to our health and performance.

The fan with the three eco's

Up to 90% of the heat is recovered


Decentrally controlled and easy to retrofit


Helps regulate room humidity


Service - FAQ - Blog - Downloads

We are here for you.

Our sales and service team is here for you.

For questions and requests, personal and individual consultations, or product training, please contact us; we will be happy to inform and advise you.

All about the Eco-Fan

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At least one...!

The number of Eco-Fans depends on the room size, layout, the number of people in the room, and individual needs.

In general, one Eco-Fan is sufficient for approximately 50 sqm² of floor area.

If we are used to keeping the room doors closed, a fan should also be installed in other rooms. For example, a single-family house has a total living space of approximately 120 m² over two floors (ground and upper floor), meaning 60 m² on each floor. In this case, one Eco-Fan on the ground floor and one on the upper floor would be sufficient. Assuming the rooms have an open layout and there is no need to keep doors permanently closed. The normal usable fresh air volume flow rate is between 80 to 200 m³/h, considering device noise levels. The higher the volume flow rate, the more audible the device becomes. In a household where cooking or smoking occurs, the air quality deteriorates noticeably, and the supply of fresh air should be temporarily increased (for example, the fan can be set from 80 to 150 m³/h). Accordingly, the fan becomes audibly louder during this time. In classrooms, seminar rooms, restaurants, canteens, offices, daycare centers, hospitals, and senior facilities, more fresh air is needed because the CO2 level rises quickly due to the large number of people present. This leads to a decrease in the concentration and performance of people in the rooms and causes discomfort.

In schools, universities, and daycare centers, the issue of "noise" can be quickly resolved. Break times are used to increase the volume flow rate, and during regular operation, the volume flow rate is reduced. In other cases, the number of fans should be adjusted to the number of people and the size of the room.

Please contact us; we are happy to advise and inform you.

In principle, a hole should not be cut into an existing glass pane.

You should order a new glass pane with the hole for the Eco-Fan from your glazier. The glazier will cut the hole directly and refill the window with gas – typically argon gas is used, with less frequency, krypton or xenon.

The hole size is 371 mm and should be positioned about 400 mm from the room ceiling.

As an alternative, a plastic insulation panel (sandwich panel) can be inserted into a frame, which achieves a similarly high level of insulation but is much more cost-effective.

For more information, please refer to the download section under: Installation Manual and/or Window Installation.

Windows with an Eco-Fan can still be used normally. They can be opened and tilted.

CAUTION: the Eco-Fan should only be turned on when the window is closed. If the window is opened or tilted, please leave the fan turned off.

It is also necessary for the window to be opened so that cleaning can be carried out. The Eco-Fan has no maintenance requirements by a specialized company, but it should be regularly cleaned. To remove the honeycomb from the outside for cleaning, the fan should be accessible from the outside or the window should be able to be opened.

For more information, please refer to the download section under: Cleaning and Care.

The installation of an Eco-Fan in the facade is also possible and makes sense in individual cases. For this purpose, a window-like frame system (400 x 400 mm) is installed in an exterior wall. A plastic insulation panel (sandwich panel) can be inserted into this frame. The frame is opened and closed using a hinge, similar to a window sash, allowing for cleaning of the Eco-Fan, as with window installation.

Such solutions are suitable, for example, for workshops, laboratories, or for large window panes – such as in a school – that need to be divided.

Refer to the drawings in the download section for more information.

The specific grant programs depend on the respective countries and federal states.

Grant programs are awarded by the federal government and federal states. The Eco-Fan is eligible for support as part of energy-efficient renovations if it meets certain criteria in the overall concept. Your energy consultant can and will assist you in this regard.

Therefore, please consult your energy consultant or the relevant authority directly.

The following links can provide you with initial guidance:

Financing programs: 

Information on local grant programs: 

Federal grant programs:

Such grant programs are subject to fluctuations and are not fixed. They are usually limited in time and funding volume. Therefore, it is advisable to inquire about them in a timely manner. If you are undertaking recognized energy-related measures in renovation or new construction and applying for funding, it is important to note that the contract with the craftsmen for these measures must not be awarded before the grant is approved, as otherwise, the entitlement to funding will be lost.

The Eco-Fan cannot freeze. The warm temperatures on the room side prevent ice from forming in the ventilation system.

What has been observed is the formation of frost patterns on the room-side glass pane of the rotating heat exchanger when the room air humidity is high enough (with moisture recovery) and the outside temperatures drop below -10°C. Without moisture recovery, ice formation can also be observed on the horizontal inner pane at outside temperatures of -3°C, but the thickness of the ice layer remains under approximately 5 mm since, after a relatively short time, dew point undershoot no longer occurs due to the room's drying out. At higher temperatures and with moisture recovery, dew point undershoots (the window pane becomes fogged) can be observed on the room-side glass pane. Whether condensate forms and drips depends on the temperatures. The condensate must run over warm parts when dripping, where it can evaporate again (cold). In the range from 0°C to -5°C, if it concerns areas where ice fog frequently occurs, icing of the fans or the drum itself can occur. In such cases, the fan should be deactivated if possible.

Blog - German versions

Moderne Heizsysteme OHNE Lüftungsanlagen mit Wärmerückgewinnung machen keinen Sinn.

Revolutionieren Sie energieeffizientes Bauen mit fortschrittlicher Lüftungstechnik.

Im Zeitalter des energieeffizienten Bauens dürfen wir eines nicht vergessen: Eine optimale Heiztechnologie ist nur so gut wie die Lüftungsanlage, die sie ergänzt...

Downloads (PDF) - German versions

The fan with the three eco's

Up to 90% of the heat is recovered


Decentrally controlled and easy to retrofit


Helps regulate room humidity


Company - The Eco-Fan

The Eco-Fan is a product of SK-Elektronik GmbH

The Eco-Fan was developed, manufactured, and distributed by SK-Elektronik GmbH in Leverkusen.

A traditional family business, founded in 1987, in its second generation and currently led by Managing Director Mrs. Natalie Kuehn.

In addition to ventilation technology, the company specializes in the development, manufacturing, and distribution of display and control electronics, as well as control and regulation technology.

At the Leverkusen site, 40 highly specialized employees develop and manufacture modern high-tech electronics that are used worldwide.


We live by this motto

In other words - in our company, there is a passion for technology and progress.

Terms like sustainability and diversity are not marketing instruments at SK-Elektronik, but a way of life:

        • All vehicles at SK-Elektronik are electrically powered.
        • A new company building is currently being built according to the highest energy efficiency standards and will be completed in autumn 2024.
        • Since 2020, we have been actively participating in tree planting campaigns in Windeck-Schladern near Siegburg.
        • Our employees come from 18 nations, and we support "The charta of diversity" (Berlin/ IHK zu Koeln).

We know that a livable future is only possible in harmony with nature and by using our human diversity as a resource for stability and peace.

We work towards this every day.


08:00 - 16:00


08:00 - 16:00


08:00 - 16:00


08:00 - 16:00


08:00 - 16:00

Your Eco-Fans...

Natalie Kühn

Managing Director 

Lars Fiß

Technical Sales

Axel Dickschat

Eco-Fan Sales

... and our team

We are happy to be there for you!

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