The furnace is always going to give off some heat. That said as posted before could be a loose duct. Might open up the space it is in, as if connected to a floor duct, it still has plugs for round ducts. One of these may have come loose and opened up. This is when aluminum duct tape becomes your best friend.
Russ & Paula the Beagle Belle.
2016 Ram Laramie 3500 Aisin DRW 4X4 Long bed.
2005 Copper Canyon 293 FWSLS, 32' GVWR 12,360#
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