michaelheerwald
New Member
I have just purchased a home that originally did not have refridgerated air but did have central heat. The best I can tell all the air blows out on the lower vents close to the floor but above each one at the ceiling there is another vent which has a cylinder in it which stops just below the opening for the grate, the forced air is coming down inside the tube to the vent on the floor, but on the upper one there is a knob which can be pulled out or turned a quarter to open the tube. My main question is why does the knob pull out like it does what is its purpose? There are also the round vents in the ceilings in most rooms! The outside unit looks rather old, like 40 years or so but the inside unint looks fairly new.