I have been reading some of the heating in winter thread and have a question. When we moved to the new house this past winter, the gentleman who sold it to us said that the furance is a dual purpose and can run on either electric or propane. I ran it on electric for the couple of months of winter we had left and haven't really thought about it since then. But I did go down and look at it today and I can't for the life of me figure out how to switch it over so it can be run on propane. I have a 500 gallon tank that is also full and the electric about killed my monthly budget when the heat was running - so I figured that I would start with propane this year and try to save a little bit of money by using what I already have. Does anyone have any ideas on how to make the switch? Is there a button or something?