Furnace duct fix

[pterrydactyl]

I'm about ready to button up the underbelly on my fiver. I'm concerned that even after putting in new insulation around the tanks that if I get into COLD weather freezing might occur. (I don't usually go where and when freezing weather would be a concern-but sometimes it happens). I have an idea to enclose the tanks with foam board, run 2 flex ducts into the box(es) with openings on the bottoms for outlets or not. Maybe reverse inflow to the bottom as heat rises.

Will add vane valves to control airflow.


Any thoughts and comments appreciated.

Terry