I have an upstairs that I don't use as living space so would like to leave unheated this winter if it makes sense and can save some money.
I know I can close the vents themselves in the upstairs rooms. I know I can also close the "valves" (for lack of a better term) in the air ducts themselves as they branch off into the various sections of the house originating from the furnace.
What I don't know is what the best approach is. Should I close only the vents, or only the valves, or both, or none? I have heard that closing off too many vents can cause the furnace to overheat. I have also heard that closing vents makes little difference because the furnace is callibrated to heat a certain square footage, and that's pretty much what it will do...the air will find somewhere to go even if the vent is closed (leaks in ducts, heat the space between the walls). I am not sure what to believe and what is just furnace folklore.
I have used foil tape to seal most of the ductwork in my house, as well as wrapped it in fiberglass insulation, only I couldn't get to the ducts that weren't accessible (in between walls). I have also weather-stripped and caulked windows and doors as much as possible, as well as added more insulation to the attic. The only cost-saving tactic I can think of is to not heat the upstairs, if it makes sense.
My goal is to save money this winter on heating costs.
If your duct system was designed properly, when you start closing off ducts not only are you not saving any money, you are driving the temperature differential up. When this happens you are taking a chance a heat exchanger problems. Not knowing your system, I am making an educated guess.
Last edited by #CARRIERMAN; 12-05-2006 at 02:47 PM.