Upon arrival technician found that the dehumidifier is being double filtered. What is causing more water to be brought out of the air and causing the drain line to fill up with too much water, which is causing the dehumidifier to build up water in the drain pan. The only thing that can be done to rectify the situation would be to remove the intake duct to the furnace instead of the plenum due to the fact that the plenum has a media filter on it.