Hi ! I have a heil furnace mod# NDGE105LF01 ser #H60148972 made in 1983.bought it with the house. Had it serviced by a professional 1 year ago .works good but I have problems with water collecting in the pan underneath the furnace from running the air cond .I cleaned the drain pipe from the crawl space but there is still a fair amount of water that does not drain and seeps horizontally inside the floor.my problem is that there is no way to reach the a frame and clean it and get to the collection pan to service it.I looked under the burning chamber and there is no way to get below that to reach the a frame heat exchanger.please help.