Staining on Factory FP damper

[Jeff Eastman]

......

[Jim Luttrall]

Looks like rust to me, water is the cause. The question is what is the source. Did you get a look at the cap?

[Jerry McCarthy]

Fireplace smoke dampers not equipped with a water-letlerr-outer usually look like that. :D

[Jerry Peck]

If they kept the home fires burning, the heat would keep that from happening. ;)