Also I had after reading the negative reviews so my skepticism as to whether the purely mechanical functioning system of Compair, actually can work as well. However, the adjustable spring seemed the key to a good fine-tuning to be, so everyone can customize the closure system individually sinem exhaust device. The adjustment was a little hard for me (had to take pliers) at the end but it worked.
The Assembly had taken me with preexisting 150er pipe in the wall about 10 minutes. Fine adjustment of the spring another 10 minutes, so I was after 20 minutes done with everything.
The Compair system may be only a couple of days in use but it is running as it should, without much effort and frills.
A perfect solution for me so far.
