Hi- we have a small length of ductwork running from a duct in the floor of our downstairs bathroom to the basement below.  Our dog peed in the floor duct and the urine corroded a small area of metal duct both inside the vent and in the elbow underneath the vent. We have tried everything to get her to stop peeing near on or near this vent, but long story short- not working.  When she pees in the bathroom and I don't have a towel down because the floor is slanted a little it goes straight into the vent and now onto my washer and dryer below.  Would this be something you could fix or replace?  None of the ductwork is hidden- you can see and access it quite easily in the basement.  We've been wrapping everything in duct tape in the meantime.