If your home has a gas or electric furnace, you’ll be running it extensively this winter to keep your home warm. There are many potential indicators that a furnace isn’t working right, from strange noises and performance issues to ever-increasing energy bills. However, one important warning sign of an impending or ongoing furnace problem is strange furnace smells.

No matter what type of furnace or heating system you have, never ignore furnace odors. In a vast majority of cases, they are a sign that something is not working the way it should. In this article, we will review some of the potential odors produced by gas and electric furnaces and whether or not those odors are an indicator of a major problem with your heater.

However, in general, strange odors should always prompt a call to your local HVAC technician for an inspection. Here in Fresno and the Central Valley, be sure to call our team at Allbritten for fast and reliable heating repair from our experienced, friendly techs.

What kind of odors can a furnace produce?

Here are some of the most common furnace odors:

  • The smell of electrical wiring or plastic burning
  • Metallic smell
  • Burning dust or smoke
  • Rotten Eggs
  • Mold or mildew
  • Pet odors
  • Sewage

As we’ll review in the sections to come, not all of these smells are directly caused by the furnace, but they may indicate a fixable issue all the same.

  1. Burning dust smell
    A burning dust smell may emanate from the furnace once you start the furnace at the beginning of the winter season. This smell is completely normal and should go away within several days. However, if the musty smell persists, try solving this problem by changing out the air filter. If the problem persists after switching the air filter, it indicates a serious problem with the furnace. In such a situation, you should immediately turn off the system and call our team at Allbritten.
  2. Metallic smell
    If you notice a metallic smell coming from the furnace, it might be due to a component inside the furnace overheating. In some cases, the smell will be similar to the burning of hot plastic, oil, or rubber. If you smell odors that suggest that something in the furnace is burning or overheating, you should immediately shut off the furnace and call Allbritten for an inspection.
  3. The smell of rotten eggs
    The odor of a rotten egg or sulfur is another cause for serious concern. Utility companies put odor-indicating substances in natural gas, which is normally odorless. So, if you notice a potent rotten egg smell in your home, it could indicate a gas leak. You need to immediately shut off the gas furnace and call Allbritten for an inspection of your system.

  4. Pet smells
    Sometimes, the smell of pet waste or hair will appear to emanate from the furnace registers. If you get a strong whiff whenever you turn on the furnace, you must inspect the floor level venfloor-levelisters. Cleaning up the mess near the vent can solve the problem.
  5. Sewage smell
    In case you notice the smell of sewage water emanating from the vents, it may be that an open sewer line or a broken wastewater line may be located near the system. A quick inspection of the external vents can help identify the source of the smell. You may have to call a plumber to resolve the issue.
  6. Moldy Smells
    A smell of mold coming from the furnace indicates a potential mold infestation inside the ductwork. You should not take mold infestation lightly. A mold infestation can degrade the quality of indoor air. It can cause people to suffer from flu-like symptoms, accompanied by sneezing and coughing.
    Through our duct cleaning service, the qualified furnace technicians at Allbritten will not only remove mold and mildew from the ducts but also take measures to ensure that it does not recur as well.
  7. Chemicals
    This is one of the most dangerous smells you could experience in your cozy home. If the scent is a distinct chemical odor and similar to that of formaldehyde, there is likely a crack in the heat exchanger component of your furnace. The heat exchanger component works by cycling heat out of the combustion chamber and then into the plenum. If this component is broken, it drastically increases the risk of fire. It may also distribute carbon monoxide fumes throughout your house.
  8. Smoke
    If you experience a smokey smell coming from your furnace, immediately turn the furnace off and open a couple of windows. This may occur when the furnace chimney (also called a “flue pipe” or “exhaust vent”) is blocked. The furnace’s combustion exhaust has to go somewhere, so it is forced into the ductwork.

Be sure to assess your safety in a situation like this. For example, if the smell is faint then open a window to ventilate and call a professional to schedule a service. If the smell is sudden or strong, you may need to temporarily leave your home and wait for a professional to come and identify the source of the smoke.

Call Allbritten to have our team inspect your furnace

Abnormal smells coming from a furnace could be one of the signs of a failing or damaged system. Here are some of the other signs of a failing furnace or that a furnace needs repairs.

When you need furnace repair here in Fresno and the Central Valley, call the locally trusted professionals at Allbritten. Our experienced, expert techs can quickly diagnose furnace odors and get your system back to running safely and effectively.

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