Cold Air Return

[delucja4]

I have a cold air return that is blowing cold air. I check other returns and the seem fine. What would cause this one return to be "blowing" cold air?

[HayZee518]

Cold air return??? It should be returning the air back to the furnace to be re-heated! In some places it is a seperate trunk line other places it uses a joist space covered up with sheet metal and then ducted down to the furnace.

[delucja4]

I don't understand it either but it's true. The vent is a cold air return and when I put my hand over the vent, cold air is coming out. It isn't "blowing" out but I can feel a cold air draft coming out of the vent.

Any ideas? Thanks.

quote:Originally posted by HayZee518

Cold air return??? It should be returning the air back to the furnace to be re-heated! In some places it is a seperate trunk line other places it uses a joist space covered up with sheet metal and then ducted down to the furnace.

[Hube]

If this return is not "drawing" air , then it obviously has some blockage in its return path back to the unit.
You will have to check all the entire path back to the unit for an obstruction of some sort, such as;loose piece of insulation,broken joint, crushed/leaky joist lining,etc.

Btw, did this return ever "draw" air in the past ? Or are you just assuming this is a connected return part of the system.
And it may sound crazy,[:I] but is the blower /fan running when you are checking it?
Also, if a fan is not up to proper speed (rpm) a poorly located return will always feel like its not "drawing",especially if located on an outside, poorly insulated wall (rim joist header.)

check it out and let us know whats up.

[delucja4]

I'll check the things you noted and let you know what I find. Thanks for the response.

[SSN596]

Some codes require a source of fresh outside air to mix with the return air. I had this on a house once. Wasn't a really cold climate, so wasn't a problem. But if you have such an intake, it could be the source of a cold draft on your return plenum.