Flex

The FLEX PP is the result of years of experience. This valve has specially been developed for those areas where the outside temperature differs a lot. In particular under circumstances of extreme coldness this valve still has an optimal performance because of the simple reason that it is very hard to become icebound in the frame of the valve.

The flap’s position at minimum ventilation (see figure) makes it impossible for condensation to pile up and freeze. Secondly there is always a warm airflow along the flap because of the Venturi effect