I Can Smell Freon From a Window Air Conditioner

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If your nose is catching the whiff of something strangely sweet emitting from your air conditioner, you could be smelling a coolant leak. It could be Freon, but Freon is simply one of several kinds of coolants that can be used in air conditioners. Whatever is at play in your machine, it's not something you should be smelling, and it's an indication that your air conditioner seriously needs servicing. If it's a sour smell, that's a different issue.


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Is It Coolant?

Any kind of chemical, sweetish smell coming from your window air conditioner is a cause for concern. It's not a DIY scenario asking for your intervention; it's a job for a certified HVAC technician. Typically, these chemical smells may smell like exhaust or may have a sweet odor like your car's coolant. Whatever the case, it's meant to be circulated within the machine's coils, not inhaled.

These chemicals are generally heavier than air, so you may get a fleeting whiff and then think it's cleared away, but it has likely sunk to the floor. Freon is a chlorofluorocarbon being phased out because of its hazardous nature to both humans and the planet. Other coolants are still hazardous to some extent and are also meant to be contained in the air conditioner's refrigerant line, not floating around your home.


What To Do Right Away

The important thing to know about window air conditioners or any air conditioner is that they all use coolant, and they all run the risk of leaking, but they're usually safe. If you think you smell any kind of coolant or chemical from your air conditioner, turn off the unit immediately and open windows and doors nearby.

Ventilate the space and you'll be fine but don't presume you've taken care of the issue. All you've done is slowed the speed at which Freon or other coolants are entering your space. Until the leak is repaired, it will continue amassing in your space. Keep in mind that fleeting exposure won't make you sick, but that's no reason to be complacent. Odds are that a leak began as too small for you to notice but has begun increasing in scope to be noticeable, and that's likely to escalate.


Under no circumstances should you continue using the air conditioner if you are smelling refrigerant of any kind.

What’s Going On?

It could be as minor a problem as a failed gasket connecting the refrigerant tubes to the compressor, through which a little gas is escaping. One of the most common causes, though, is when metal slowly corrodes from the formaldehyde or formic acid that can be present in the coolant. It can cause pinholes to form, through which the gas emerges.


Another problem can be poor air conditioner installation or factory defects. Something may have gotten knocked or crushed, and it could compromise the system.

If your air conditioner remains under warranty, then you need a certified HVAC technician to make repairs, or your warranty could become null and void. If it's not under warranty and coolant lines have corroded considerably, your window air conditioner may need replacement.

Symptoms of Refrigerant Poisoning

If you suspect that you or your family has inhaled too much refrigerant, you should call the National Poison Control Hotline at 1-800-222-1222. If the symptoms are acute, call 911.


Freon inhalation can be fatal, as it can fill your lungs and prevent you from getting oxygen. Mild symptoms include dizziness, headaches, vomiting, nausea, coughing, and/or irritation of the eyes, ears, and throat.

More serious symptoms of poisoning may include fluid buildup or bleeding in your lungs, vomiting blood, irregular heartbeat, loss of consciousness, loss of mental faculties, seizures, and difficulty breathing.



Steffani Cameron is the daughter of a realtor and interior decorator mother and a home contractor father. Steffani is a professional writer with over five years' experience writing about the home for BuildDirect and Bob Vila. Raised with a mad love for decorating, Steffani gave up her Art Deco apartment to travel and work remotely for five years. She's in love with experiencing traditional decor around the world, including stays in Thai teak plantations on the Mekong River and cave homes in Turkey.