Why Does My AC Smell Like Chemicals?

It’s the hottest time of the year in Minnesota, and you’re counting on your air conditioner more than ever. With beads of sweat rolling down your neck, you switch on the AC and start to feel that nice, cooling breeze– only to discover that the air flowing out smells like chemicals.

What gives?

Unfortunately, this situation is all too common– and it always seems to happen when you need your air conditioning the most. But don’t worry, the major reasons your AC smells like chemicals include the below and are simple to fix:

Refrigerant is a critical component of your air conditioner as it removes hot air from your home’s air, cooling you down. Evaporator coils in the indoor AC unit house the refrigerant, and the chemical agent makes its way around your house via refrigerant lines. Unfortunately, these lines can crack over time and leak refrigerant.

What does refrigerant smell like? Usually, it smells sweet and almost like chloroform. Other key signs of a refrigerant leak include:

• Warm air coming from your AC
• Ice collecting on the refrigerant lines
• Weird noises coming from the AC unit, like a creaking or bubbling

The worst telltale sign of a refrigerant leak is atypically high electric bills.

AC refrigerant problems are common, and waiting to address them is never a good idea. If you suspect you have a refrigerant leak, it’s best to contact a professional right away. Only a certified pro should handle this substance because it’s otherwise dangerous to do so.

A thick layer of dirt on the evaporator coil prevents the refrigerant from absorbing heat properly. As a result, your AC can’t cool or dehumidify as well as normal.

When dust and dirt on the evaporator coil come into contact with moisture in the air, mold and mildew can grow. This growth creates a musty or ammonia-like odor.

You could try to clean the coil yourself, but they are fragile and easily damaged. Because AC cleaning usually requires special equipment and training, we recommend hiring an expert technician to do it for you.

As we’ve mentioned above, your air conditioner doesn’t just cool your home—it also dehumidifies it. Where does all the moisture go? The AC collects the accumulated moisture into a drain pan and then funnels it out of your home via a condensate drain line.

However, when the drain line gets clogged with dirt or debris, all the moisture ends up backing up into the drain pan and sitting. As you can imagine, the drain pan lives in a warm and dark area of the AC system, leading mold and mildew to grow.

You can tell if you have a clogged condensate drain when your AC starts short cycling AKA running for a short period, shutting off, then restarting. Another indicator is if you see water pooling around your indoor AC unit.

When most people smell chemicals in their AC, they don’t realize that the most straightforward answer could be the right one. Are you smelling chemicals because there are chemicals open near your indoor air handler? If there is anything open with an odor near the air handler, your AC will pick it up and distribute that smell throughout your house.

Most AC units in the Twin Cities have air handlers in basements. Many homeowners also store their cleaning supplies, chemicals, and other odds and ends in their basements. You'll want to double-check the basement for open chemical containers if you notice an odd odor. For example, your cleaning supplies might have tipped over near the air handler, and your HVAC system pumped the smell throughout your home.

To resolve the issue, close any open containers, clean up the spill (make sure to turn your AC off for this unless you want a repeat of the chemical spills), and remove anything that could cause an odor away from the indoor air handler.

MSP has served the Twin Cities community for more than 100 years with our fast and friendly service. We provide same-day air conditioner repairs for all makes and models.

With over thousands of 5-star reviews, honest upfront prices, and a dedication to making your home as comfortable as possible, we are committed to getting the job done right—the first time. Your 100% satisfaction is our guarantee.

Call us at (651) 228-9200 or click the button below for same-day service!