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Air Conditioning Checking

Air Conditioner Smells Bad When Turned On

Updated: Feb 10, 2023

As a Florida homeowner, you probably praise our air conditioning systems for keeping you cool and comfortable year round. But if you’re greeted with a foul odor whenever your AC kicks on, your system can go from MVP to enemy in an instance.

If you’re experiencing a bad smell coming from your air conditioner when it turns on, fear not. There are a few reasons why this occurs, and luckily the remedy is simple. Read on to learn the most common reasons your air conditioner smells bad when turned on and what you can do about it.

Girl Fed Up With Air Conditoner Smell

Bad Smells Coming From Your Air Conditioner

When something goes awry, it can cause different odors to come from the AC vents in your home. Identifying the bad smell is the first step to figuring out the underlying problem.

1. AC Smells Like Old Cigarettes

The problem: You turn your AC on, and your house smells like an old dive bar. Gross!

No one wants the home to smell like old cigarettes, but it’s a common issue amongst homeowners—especially for those who own older homes. If you or someone in your household smokes cigarettes, or the previous owners smoked inside, your air conditioning system can suck the fumes into the evaporator coil. As the odor permeates the ductwork, the evaporator coil blasts the smell of old cigarettes throughout your home every time you run the air conditioner.

The solution: A simple evaporator coil cleaning can help rid the cigarette residue.

2. AC Smells Like It’s Burning

The problem: You turn your AC on, and it smells like something is burning, only it’s not dinner.

The burning smell is one of the most commonly-experienced scents that can come from your AC. If you have turned the heater on for the first time in awhile, it’s likely settled dust burning and nothing to worry about. However, a burning scent can be indicative of a mechanical problem with the AC fan or compressor.

The solution: Turn off your air conditioner and check that the burning odor isn’t coming from the actual air conditioning equipment. If it is, call your local HVAC professional for help.

3. AC Smells Like Dirty Socks

The problem: You turn your AC on, and your home begins to smell more like a locker room than that new candle you just bought.

Say hello to dirty sock syndrome. When stagnant water collects within your AC, it can cause a mildewy scent to permeate through the vents every time your system kicks on.

The solution: You can fix this smelly problem by cleaning the drain pipe within your AC system. If anything is preventing the water from draining properly, remove the blockage or have your local HVAC technician take a look.

4. AC Smells Like Rotten Garbage

The problem: You turn your AC on, and your house smells like rotten garbage.

Perhaps one of the foulest smells on this list, if your AC smells like rotten garbage every time it kicks on, you undoubtedly want to fix the problem and fast. This scent is likely caused by a bird, mouse, rat, or other rodent that has died inside the ductwork of your air conditioning system and is beginning to decompose.

The solution: A decomposing animal is not a comforting thought, but luckily it’s not particularly dangerous. Still, be sure to local your local HVAC technician as soon as possible to remove the critter.

Air Conditioning Repair in Orlando, Florida

If bad smells coming from your AC are making your home less enjoyable, the professionals at Energy Air want to help. Our team provides quality air conditioning replacement services at economical prices. We understand how important your air conditioning system is to the overall comfort of your home, which is why we provide 24/7 emergency repair service. Contact us today to learn more or schedule your appointment online.

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Contact Energy Air

Whether you need a single air conditioning unit installed or a complete air conditioning system retrofit, our team of HVAC experts will handle it. Have questions or would like to discuss your project? Give us a call today to talk to one of our friendly team members, or schedule your appointment online.

Orlando: (407) 501-6275 | Tampa: (813) 314-7261

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