Q: I turned on my furnace for the first time this year, and it made the whole house smell musty. I checked the filter and found it caked with dust, so I replaced it with a new filter, and the indoor ...

Add Yahoo as a preferred source to see more of our stories on Google. A man kneels while pulling a dirty filter out of a furnace - Backyardproduction/Getty Images Changing your furnace filter is one ...

If your heating bill has recently climbed, or your furnace seems to be running more than usual, the problem could be something simple: a dirty furnace filter. It's easy to overlook, but this small ...