Why Does My Air Conditioner Smell: All You Need To Know

Few things can be more frustrating than returning home to enjoy a reprieve from the summer weather under your air conditioner, only to be greeted by a pungent smell as the AC starts running. The default action usually means seeking out the source of the smell until you realize that it’s your air conditioner.

In that scenario, you’ll find yourself asking, “Why does my air conditioner smell?” As the leading air conditioning repair experts in Inverness, FL, and the surrounding areas, we’ve seen many possible reasons for air conditioner smell. We’ll look at them in this article and the accompanying solutions for each of them.

The Top Causes of Air Conditioner Smell

Some of the top causes of air conditioner smell include the following:

Mold and Mildew

Mold and mildew aren’t the worst smells you’ll perceive from your air conditioner. However, it can still become annoying and a reminder that you have a serious problem on your hands. Mold growth should have you worried. It is bad for your health and can cause extensive property damage.

Mold and mildew will thrive in and around your air conditioning unit, with excess humidity around the system.

You can avoid this problem by ensuring your air conditioner’s condensate drain lines remain free from blockages and the system has no water leaks. Schedule HVAC tune-ups at least twice a year to catch any problems that may cause excessive humidity around your air conditioner and encourage mold growth.

Away from the air conditioner, you should also ensure you find no possible causes of excessive humidity or water damage inside your home. Even if the mold growth doesn’t start from your air conditioner, it can still make its way into your air ducts from other parts of your home, causing that unwanted smell.

If you have an unfinished basement or crawlspace, you should explore ways to cover up the exposed soil. You should also consider installing a whole-home dehumidifier. Most importantly, you should deal with any existing mold and mildew growth in your home to keep them from spreading.

Dirty Air Conditioner Parts

If you have dirty evaporator coils and clogged condensate drain pans, your air conditioner will deliver that stinky feet or dirty socks smell as it runs.

Similarly, if you had a smoker around for a while, you may smell stale cigarette smoke when your air conditioner runs if your air filters and evaporator coils trapped enough of the smoke residue.

In many cases, when we hear, “Why does my air conditioner smell?” it often comes down to dirty air conditioner parts.

Fortunately, consider the solution as simple as requesting a professional cleanup of the HVAC system and changing the air filters. You can keep the smoke smell from returning by encouraging any smoker in your home to only smoke outdoors.

Burning Air Conditioner Parts

When AC units smell like something is burning, it likely indicates something is indeed burning or overheating. You may have an overheating motor, a wiring issue, or other mechanical problems.

If the smell resembles gunpowder, you likely have a burning or fried fan motor or circuit board. The first thing you should do is turn off the HVAC system immediately from the breaker box and inspect the damage.

If you see signs of the burning continuing, call the fire department. When you get the all-clear to re-enter the home, invite an HVAC technician to inspect your air conditioner and complete any necessary repairs.

Sewer Problems

Do you perceive the smell of sewage while your air conditioner runs? You probably have dry P-traps. Run water through all your sinks for a while to fill the p-trap and create a seal against the sewage smell.

If the p-traps aren’t the problem, you likely have a ruptured sewer vent or backed-up sewer line. Either way, you need to call a plumber to evaluate the problem and propose solutions.

Decomposing Dead Critter

The smell of a rotting rodent in your air duct system ranks as one of the worst smells you’ll ever have to deal with. You also can’t wish it away because the smell will only intensify as decomposition continues.

So immediately after you perceive the smell, turn off the air conditioner and call in an air duct cleaning company. Your local HVAC technician most likely offers this service. Contact them to get your air ducts smelling fresh again.

Next, you should work with a pest management company to keep critters out of your air ducts. It’s the only way to prevent a repeat.

Gas Leak

Can you notice a rotten egg smell while your air conditioner runs? If so, you could have a gas leak. Natural gas is odorless, so manufacturers add mercaptan to give it that familiar smell that will help homeowners know when they have a leak.

Follow these steps in this situation:

• Turn off your gas supply at the main valve (or call your gas company to do it if you can’t find a valve)
• Open all your doors quickly
• Evacuate the building
• Turn off all electrical appliances and any fire source
• Don’t use a lighter or matches in the house
• Call your gas company

The gas company will check the source of the gas leak, fix it, and turn the gas back on for you.

Don’t Ignore the Air Conditioner Smell—Get Expert Help Today

A bad smell coming from your air conditioner can either be mildly annoying or impossible to live with. In the latter case, most people will seek immediate help. However, when the smell is only mild, some homeowners will attempt to mask it with scented candles, aerosol sprays, and scent diffusers.

However, that puts your air conditioning system at risk. If you find yourself asking, “Why does my air conditioner smell?” you should seek professional help to ensure you have no underlying problems that may lead to costly repairs.

Save yourself the stress and call the Fast Air Repair team in Ocala, FL, today at (352) 290-7968 to check out the source of the smell and to find any signs your AC needs repair.