I've got a natural gas Miller Furnace. This past weekend when I came home, the house was cold (62-ten degrees below setting) and I couldn't find anything wrong, so I just turned off and on the furnace, well it fired back up, but was only blowing air, not heating it up. There was a flame were it should be. I did the off on trick a few more times and same result. Called a guy and waited for a call back. While waiting I turned on the oven to try and heat the house, and it helped, but out of the blue the furnace started working and blowing hot air again. Time frame was about 40 minutes...anyone have an idea on why? and should I be worried. Oh and the furnace is just 2 years old.

If it stopped working correctly once it will probably stop working again. The problem you are going to have is that the problem is intermittent in nature and that will make it difficult to diagnose.