In the middle of our living room is a return-air vent. It goes straight up to 2 of the bedrooms upstairs also. When the furnace kicks on, the noise coming from the vent down here is rediculously loud, almost to a point where nothing else is distinguishable above the wind sound. The furnace's...

I have a gas furnace that has a vent coming from outside and is spliced into the cold air return. What is the purpose of this? Does the cold air affect the efficiency of the furnace? Can I remove it or does it need to stay in place?

I have a portable air conditioning unit and I was wondering if it would be OK for me to set the exhaust tube down a return air vent because I don't want to set up my portable air condition at the window. Too many bugs get through if I leave the window open.

All- We recently moved into a home that had been flipped... some of the work was done OK, the rest not so well. I have spent the past couple of months reworking, repairing and finishing the work the flippers did. One of the issues has to do with our return air vents. We have central air...

We just purchased a home built in the 50's, and the grill for the return air vent in the hallway is sealed with tape and aluminum foil. It seems to be pretty tight, as if whoever sealed it had a really good reason to do so. What would the reason be for doing this? We can't decide if we are going...