Why A Sweet Smell Coming From Your Air Conditioner Should Concern You

As you sit down to relax, you smell something sweet, but not the good-tasting kind of sweet ... rather, it's a chemical-like, soft odor. Once you pinpoint that it's coming from the air conditioner, you may be worried. Any type of odor emanating from a working system is cause for concern, and while your mind may be racing to figure out what got shoved into the vent, the problem may be related to the coolant in your air conditioner.

Odors coming from the vents throughout your home can be due to something in the ductwork, and it is possible that a critter is lurking in there or dirt and debris have built up. Most often, these odors can be described as musky or moldy. If what you smell has a chemical-like sweet scent — like a bad maple syrup — that's cause for concern and may require repairs right away. That means the smell isn't coming from the ductwork, but rather the air conditioner itself. If it's coming from an older air conditioner that uses Freon, it's time to give a professional a call. Freon isn't typically something homeowners can fix themselves, but it still helps to understand what's occurring. As one of the most common air conditioning failures for older systems, Freon leaks shouldn't be put off. 

What is coolant in an AC?

Freon has been banned from use in new systems since 2010, but it's still found in homes here and there. Other air conditioner refrigerants, including more commonly used hydrofluorocarbons, contain coolants that have a pungent scent to them and often smell quite sweet or fruity.

Refrigerants are critical. Within air conditioners, air passes across a set of coils to cool. Within those coils is a chemical refrigerant capable of pulling out the heat from the air as it moves across. As it absorbs heat, the refrigerant will turn from a gas to a liquid before it exits out the back of the AC and out the house's window. Before reaching the outdoors, a large fan works to heat up that air before it is exhausted.

As the cooled air moves through your home, the coolant moves back into a gas form. As this process repeats, you should not smell anything. If you do, that means there's a leak present, which means that somewhere along the path, the refrigerant is getting out of the system. The exposure to the air causes that sweet smell that travels through the ductwork to other areas of your home. 

Fixing a Freon leak

Don't put off getting a heating and cooling technician into your home to inspect and repair a sketchy-smelling system, especially if your system still uses Freon. Keep in mind that your HVAC system can make you ill if the problem continues. Freon can be dangerous to manage on your own. Though there are some handy and experienced DIYers that may be able to purchase the proper kit and refill the product themselves, many wholesale suppliers will only sell to licensed or certified HVAC companies. That's because this substance can be deadly when inhaled or during overexposure. So, more than probably, you should let a professional HVAC team handle the situation.

Knowing when it's time to recharge your air conditioner is also an important step in this process. Often, a lack of refrigerant will have other signs more likely to impact day-to-day life, such as an AC that is blowing hot air rather than cold. You may also notice that your system is running longer as it tries to cool down your home — or maybe it doesn't really get all that cool at all. Finally, you may notice your air conditioner is running a lot more, leading to higher energy bills. With these signs and the sweet smell, your HVAC technicians will need to take a closer look at the refrigerant in your system, fix the leak, and then recharge the coolant.