HAF (High Air Flow) honeycomb filters are based on a microstructure and an electrostatic charge that attracts even the smallest particles.

So even though the filter is sparsely structured, the particles are trapped inside the filter by the static charge, and only filtered fresh air flows in.

When should the filter be changed?

The filtering performance of a window filter is greatly influenced by the frequency of replacement. It is important to change the filter at least two times a year.
Although a filter may appear clean at first glance, its performance deteriorates significantly over time as invisible micro-particles clog its static surface.
Prepare well in advance for the pollen season by replacing clogged window filters from winter with clean ones. This will allow more pollen to enter the filter and keep the indoor air fresh all spring long.  

Does the window filter affect the operation of the valve?

The open cell design of the filter ensures low flow resistance. The filter therefore has little effect on the air flow, only on the cleanliness of the air.
At the Suodatinkeskus you will find window valve filters for many models. Take a look at our range and ask our experts for more information!