I have a Trane XV80 with downflow furnace filters. According to the Trane manual I am suppose to install 2 filters in a V position (as shown in the help file):
1) Do I need to do this? When I moved in to this house there was a single 16 X 20 X 1 filter laying across. I have been using a single filter for the past year (until I finally read the manual).
2) Are there any better filter systems I should use? The 16 X 20 X 1 filters seem very hooky. Even using 2 in the V seems clunky. Is it ok to buy a thicker filter say 16 X 20 X 2 or 4 and lay it across? Or will this mess up the furnace?