Trane XR80 (TDD1) furnace filter sizes
XR80 (TDD1) furnaces take 14 x 20 x 1 or 16 x 20 x 1 filters, depending on cabinet width and return.
Pick your full model number below for the exact size.
2 filters, each 14 x 20 x 1 (downflow top (external, in return duct)) or 2 filters, each 14 x 20 x 1 (downflow top (external, in return duct))
2 filters, each 16 x 20 x 1 (downflow top (external, in return duct)) or 2 filters, each 16 x 20 x 1 (downflow top (external, in return duct))