I've got a register that does not appear to be blowing any air. The register is located approximately 4 feet from another register that is blowing just fine. I can hear the furnace working through the register that is not blowing, yet nothing seems to be coming out. This suggests to me that the register is blocked, but Im not sure how to test it.

Any suggestions would be much appreciated.

Thanks,
Adam

Type of ductwork? Slab, basement, ceiling? Mirror and flashlight works good. Could be a closed damper in that run.

The register is on the 3rd floor of the house on the floor. The register is located approximately 12 inches from an external wall of the house and is made of galvanized metal. Upon dropping between the floor joists the duct angles towards the exterior wall.

Thanks for your help... I'll try the mirror and see what there is to see.

Adam