I was cleaning the natural gas furnace ducts and then the cold air side... found several yards of wax paper in the cold air returns and am mystified. I know this is an old house (circa 1930 build), but have to ask... did someone use the cold air return for a trash can or is there any reason they would have put wax paper in the cold air return?
The house is MUCH better with air quality now that the spider webs and dust/dirt is gone.
Maybe there was some old school reason for the wax paper-to keep dust down?

there is no good reason, it's a firetrap feature.

it is borderline possible that somebody was trying to coax more heat from an "octopus" furnace in dire circumstances way back when, and didn't know that to get air into a room, you have to get air out of it as well.

enjoy your cleaner air!

Firetrap? Even on the cold air return line? Ahh either way it is gone and Thanks for the reply-wax paper in the return made NO sense to me either.

Maybe someone wanted to check for airflow using wax paper, and it got sucked into the return duct.

I can't see any reason for putting it in there intentionally either.

Thats an interesting find...