Why Are There Bad Smells Coming From My Furnace?

When it’s freezing outside, furnaces are important for keeping any business or home warm. To extend its lifespan and protect your safety, it’s important to maintain such a heavily relied-upon piece of equipment.

Normally, there is nothing to worry about if your furnace smells terrible when you turn it on after the hotter months. However, if other scents emerge or last longer than a few days, this can indicate a more serious issue, which might require an emergency repair or furnace replacement in San Fernando, CA.

Why Does My Furnace Have An Odd Smell?

Here are a few odd smells and their potential reasons why your furnace might be releasing:

  • Burning smell
    Your furnace gathers dust throughout the warm spring and summer months when it is inactive. This dust will burn off when you initially turn on the furnace when the temperature drops, possibly leaving your home with a faint burning stench. This odor is quite natural and will disappear as you use your furnace during the winter. You may be dealing with a deeper issue if your furnace emits a strange odor for longer than a day.
    A clogged chimney may cause an odd or amusing smokey smell coming from a furnace. Smoke cannot pass through a clogged chimney. If the chimney is blocked, smoke will move through the furnace ducts and contaminate its surroundings. When this occurs, turn off your gas supply line, switch off your furnace, and get assistance from our professional.

  • The smell of the new system
    Due to the protective oil coating within, new furnaces may emit an unpleasant stench when initially used. This barrier must burn off, just like a brand-new oven. This stench shouldn’t persist longer than a day or two and doesn’t indicate a more serious problem.

  • Plastic smell
    Your furnace’s plastic smell indicates that one or more parts are broken. The furnace’s overheating can start a fire if it is not attended to. When you initially turn on your furnace, if it starts to smell like plastic, turn off the heating system and call an HVAC professional to take a look.

  • The odor of rotten eggs
    This is most likely the alarming odor coming from your furnace. To alert customers to gas leaks, gas companies add a chemical to natural gas. There may be a severe gas leak nearby if you smell something odd, like rotten eggs. You need to leave your house immediately to protect your health. Contact our HVAC expert, and wait for clearance to enter the home.

  • Oil odor
    Although it might not be a major deal, an oily smell from your furnace may require professional care. An oily smell could signify that your furnace’s filter needs to be changed. However, if the odor persists for more than a day, it can indicate that there has been an oil leak. Call our specialist immediately to see if this is the situation.


If you are looking for furnace repair services contact Santana Air Inc. Our HVAC experts will provide you with the best furnace services in San Fernando, CA. Our expert technicians will guide you through the process. Contact us today!

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