Demand-led technology is patent pending

2020 raised awareness of air hygiene beyond our sector. With its air purifier, Kampmann is making a significant contribution to combating the coronavirus pandemic. Grade H14 HEPA filters can now be retrofitted, on request, to enable Venkon fan coils (indoor recirculating air units) to help reduce the viral load in room air. New units can also be equipped with this accessory, if required. The ingenious idea: the particulate filter unit (HEPA) is only activated by a motor upstream of the air intake of the recirculating air unit when required.

The cavity around the air intake provides sufficient space for the insertion of a filter and motor. Control is provided by a manual switch or by different automation or presence controls. This enables Venkon fan coils to provide the requisite flexibility: air hygiene, energy-efficient, comfortable and inexpensive to operate! Kampmann has therefore applied for a patent for the technology.

Why is the HEPA filter in the Venkon fan coil not continuously operational?

The core function of a recirculating air unit, possibly installed in hotels or offices, is to control the temperature of the room air. A retrofitted high-performance filter, which is permanently installed upstream of the air intake, causes a higher pressure loss, and hence loss of performance when operated constantly. It is crucial that the HEPA filter is used when it is needed. New units can be designed in the usual way in line with project requirements, that is to say day-to-day operation without a filter. The motorised HELP filter unit can then be included as an accessory kit.

left: Temperature control without a HEPA filter right: Demand-led filtering with a HEPA filter

Benefits of demand-led activation at a glance

  • Good air hygiene – the room air is only drawn through the filter and cleaned when required
  • Power consumption of the units remains low
  • Noise emissions only rise with demand-led activation: usually quiet in normal operation
  • Infrequent filter change
  • Lower operating costs compared to continuous use of the filter


Demand-led filtering is extremely important and sensible in hotels. The particulate filter is activated as soon as the hotel guest leaves the room and the hotel bedroom air is purified for the room service personnel. An actuator disengages the filter unit from the air intake at the latest when the next guest checks in. The room air then no longer flows through the filter, but instead directly into the heat exchanger of the Venkon fan coil. The unit continues to work quietly and energy-efficiently. Hotel guests can therefore rely on clean air, at the same time enjoying the comfortable climate of well-being. This example demonstrates that linking the system to the hotel’s booking software fully exploits the benefits of the system.

Offices can therefore also be cleaned several times a day. The physical increase in noise emissions during filtering is only temporary.

What sets the HEPA filter apart?

Grade H14 HEPA filters (High Efficiency Particulate Air filters) comply with the requirements of DIN EN 1822. They filter out 99.995 % of the suspended particles contained in the room air. This results in clean ambient air, free of viruses, such as Sars-CoV-2, bacteria, spores, pollen, household dust or mildew.

Do you plan to procure a retrofit kit or would you like individual advice on a new design? Simply get in touch with us. Find your personal contact here.