Inside my HVAC (past the horse hair filter) is a large gap before the air hits the radiator. The inside of this area appears to be lined with some kind of fiberglass insulation.
I asked maintenance why it looked the way that it did; I thought it was mold at first but was told that it's just dirty. It does appear dry and I agree that it's probably just dirty.
I'm also concerned that the fiberglass material looks like its deteriorating and the fact that its locates past the filter where it can get sucked up and into the ductwork.
My questions are: is this the right kind of insulation for this purpose and does it need to be replaced?
It looks like a very old unit but I can't find any indication of when it was installed.