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Blogs from March, 2021

Furnace Smells

Even if your furnace has been running at peak efficiency this winter season, it is still possible for it to release a funky odor. The good news is that oftentimes, furnace smells are nothing to worry about, and can be taken care of with some simple cleaning and maintenance. Other times, however, that odor coming from your furnace could represent a serious danger to your household. Keel reading for everything you need to know about furnace smells, and remember that for all your furnace repair and installation needs, you can always contact our highly trained HVAC experts at H.L. Moe Co., Inc.

What to Know About 5 Common Furnace Smells

  1. Sulfur/Rotten Eggs: A sulfuric, rotten egg-like smell emerging from your furnace is a common sign of a gas leak. Natural gas is one of the most common furnace fuels, as it is extremely combustible and very energy-efficient. However, when an internal problem occurs in your system and the gas isn’t vented correctly, it can pose a severe hazard to anyone in your home. Watch out for symptoms of a gas leak including nausea, dizziness, fatigue, headaches, and confusion, and make sure to get your family out of the house and call a professional ASAP if you believe you are experiencing a gas leak. You should also avoid anything flammable in this scenario, as even striking a match during a gas leak could cause a deadly house fire.
  2. Electrical Burning: We have almost all smelled the distinct odor of burnt wiring before. You may notice this scent wafting out of your furnace as the blower fan ages, and starts to draw more electricity. This can cause sparking in your unit’s wiring and insulation, potentially leading to a fire inside your furnace that may spread to surrounding objects. Your furnace will not even be able to function without a working blower fan, so if you smell burning coming from your system, call right away to have this component (or your entire furnace) replaced.
  3. Diesel Fuel: Have you ever noticed the smell of diesel coming out of your furnace, similar to the smell of fuel you would fill up a car with? What you are actually detecting is an abundance of oil. Oil is another common and reliable furnace fuel, but it is key not to over-fuel an oil-based furnace. When this happens, a kind of fog can form in the system, which will then start to burn when the heating element is turned on, leading to that diesel fuel odor you are smelling. Too much oil is another thing that can turn your furnace into a fire hazard, so be careful when refueling your system, and always call a technician if you pick up on this scent in your home.
  4. Dirty Socks/Gym Smell: You know that smell that hits your nose when you step into the locker room at the gym? That sour odor that’s a mix of sweat and dirty socks? What you are smelling is an accumulation of moisture, and the bacteria that comes with said moisture. It is possible to find this stench coming from your furnace if excess condensation has built up on the coils. This tends to happen when your thermostat is frequently turned up and down. Make sure to monitor your thermostat use to prevent this odor from occurring. Luckily, this nasty smell is fairly easy to get rid of, as long as you call an experienced technician for a furnace cleaning.
  5. Dust/Must: You will usually smell a musty odor coming from your furnace after you fire it back up following months of disuse. In the period where your unit has been dormant, it is likely to accumulate a fair amount of dust and debris. When you then turn it on, that dust will start to burn off, releasing that musty smell that’s now pervading your house. The good news is that although this smell isn’t pleasant, it also isn’t harmful, and can usually be gotten rid of by replacing your furnace’s filter (this should be done annually anyway, to strengthen system performance and improve indoor air quality.) To prevent mustiness in your furnace, you can also sign up for an HVAC maintenance plan with our experts at H.L. Moe Co., Inc. We’ll provide regular furnace cleanings, inspections, and tune-ups to keep your unit running at peak efficiency for as long as possible.

To schedule furnace maintenance or to request another service, call (818) 396-8002, or contact us online.