If you live in a colder climate, nothing is more frustrating than turning on your gas furnace on a cold day only to discover strange odors coming from your vents. While some smells from your gas furnace can be alarming, others may go away on their own, and here are some examples of smells that may be coming from your gas furnace, what they mean, and what you can do about them, and if you smell rotten eggs or sulfur coming from your gas furnace, you may have a gas leak, and natural gas is naturally odorless, but gas companies use additives to alert people of its presence. If you detect the odor of rotten eggs or sulfur coming from your gas furnace, switch it off immediately and notify your gas supplier… If you smell burning dust when you turn on your gas furnace for the first time in a year, it’s a natural occurrence. Your gas furnace can collect dust during the summer months when it’s not in use, and when you turn it on in the winter, the dust can ignite, leaving a smell of burning dust coming from your gas furnace. Don’t panic if you smell burning dust coming from your gas furnace; it generally goes away on its own. You may have a mechanical issue if you smell burning oil or metal emanating from your gas furnace. If you smell burning oil or metal emerging from your gas furnace, turn it off instantly and notify your heating and air conditioning provider to avoid additional damage.