Most types of furnaces emit odors, but usually at such negligible levels that you barely notice them. However, sometimes your unit may give off an odor that you simply can’t ignore. In such cases, these odors are indicators of serious problems that require the attention of an HVAC professional. In this blog, local furnace repair contractor Efficient Systems discusses some of the various smells that may come from your furnace.   Rotten Eggs — A rotten egg smell is associated with high sulfur levels. This smell is so repulsive yet recognizable that it’s used as an additive to gas to highlight its presence in the air. If you get a whiff of this in your home, get everyone out of the house immediately and call your gas company. Keep at a safe distance until a gas technician pronounces it safe. Bring in a trusted HVAC technician to make sure that the leak from the furnace won’t occur again. Also, consider investing in a gas alarm system for your home. Electrical or Overheating Smell — This type of smell is often described as being similar to burning plastic, hot metal or melting rubber. Such a smell typically indicates that something is burning in the furnace apart from the heat exchanger, where fuel is supposed to burn. Cut the power to your furnace—switch it off at the breaker if you have to—and schedule a furnace repair appointment. Smoky — Furnaces typically emit a burning odor during the first 24 hours after you initially fire it up at the start of the season. This smell comes from the burning dust that may have accumulated in the furnace since the last time it was used. However, it’s a different situation if you smell smoke days after you’ve started using the furnace. If this is the case, turn off the furnace immediately, and shut off the gas supply as well. Inform your HVAC technician of what you’ve done so far, then schedule a repair appointment. Musty — Mold and mildew in the air ducts can result in a musty smell. It’s important to properly shut down your heating and cooling systems at the end of their respective seasons to prevent moisture from getting trapped in the ductwork and leading to mold amd mildew growth. A thorough cleaning of the air ducts can help relieve your home of such odors. Schedule a duct cleaning appointment every five years to prevent this from happening. Call Efficient Systems for All Your Heating Needs If your furnace is emitting any of these odors, call Efficient Systems to schedule a furnace repair. Give us a call at (317) 293-6510 or fill out our contact form. We serve customers in Indianapolis and nearby areas.