Hi,

I'm having an issue with a few rooms in my house that get very little heat coming out of the vents (the heat for these rooms come from the same line). I stuck my arm in the vent to see if there is that valve that blocks the heat or to see if there is a blockage but there is nothing there so I'm not sure why little heat comes out of one room and lots of heat comes out of another.

Please help.

First,how is the filter? Make sure you don't have any manual damper that may be closed to that area.