Hi. I have a natural gas furnace that's about 7 years old, in a house I just bought this summer. Today I was noticing that it was pretty cold, so I turned up the furnace. It went on, but after a while I noticed that there was no air coming from the vents. I tried to turn it off and on again but there was no change. I'm not quite sure what's wrong, but it seems to me that it's a circulation problem. When I checked the furnace, I wasn't sure what I was looking for to see if it's working. There is no heat coming off it, but it's definitely doing something because it's humming along as normal. Does the switch I have to the furnace from my fuse box control the furnace power, or just the power of the fan? If I turn it off and then on again, will that mess up my pilot light and be risky? (I had some friends over and one of them may have turned that switch off, thinking it was a light switch--that is a possibility if that switch just controls the fan). As you can tell, I know little about my furnace... until now, I lived in blissful ignorance. Thanks for any help. Dan.