It is used to control the power of air flow in the chimney, and prevents the ingress of combustion products into the room
It has a control range of 10 to 35 Pa
On the handle there is a scale for pressure setting in the mentioned range
To adjust it is enough to pull the regulator to the desired graduation with already mentioned pressure value and fix locking screw
The diameters produced: 150 mm, 160 mm and 180 mm