Why Does My Air Conditioner Smell Like Vinegar?

After a hectic day outside, we are all looking to get home, turn on our air conditioners and bask in the joy of a climate-controlled house. What happens if you find your AC smells like vinegar on turning it on? 

You are disappointed and may want to get to the bottom of this. Luckily, I have prepared all you need to know about the problem you may be dealing with and solve it.

If your AC smells like vinegar, it probably accommodates loads of organic material in the vent or air filter. Unchecked ACs provide a suitable environment for mold and bacteria growth creating a sour vinegar-like smell. The smell is what the AC lets out once you turn it on, making your entire space smell like vinegar. 

Is It Dangerous If Your Ac Smells Like Vinegar?

Sometimes, you may want to ignore your AC smells. However, you need to ask, is it dangerous if your AC smells like vinegar? It is dangerous to your health if your AC smells like vinegar. 

It puts you at risk of breathing and respiratory problems. The vinegar smell may emanate from a mold and mildew buildup, putting you at risk of elevated allergic reactions, wheezing, coughing, and even fatal pneumonia.

You may also experience chronic fatigue and headaches. Your AC smelling like vinegar can also result from ozone release, which is dangerous to your health. Breathing in a lot of ozone can harm your nervous, respiratory, and cardiovascular systems. 

Causes of AC Smelling Like Vinegar

I know you are eager to know the source of this horrible smell. These are the top reasons why your AC smells like vinegar.

Mold and Bacteria Infestation 

A properly running AC system creates condensation as the evaporator coil cools warm air to bring you the desired cool breeze in your home. The system’s drain pan then drains away from the drips from the condensation. If the drain pan is not expelling, the condensation drips fast enough; it provides a warm and moist environment for mold and bacteria growth. 

If you fail to clean the AC ducts regularly, mold and bacteria build up in the AC air ducts. They form colonies with a vinegar odor that will be blown into your home as the AC system functions. Breathing in mold and bacteria can be detrimental to your respiratory health. 

AC is Emitting Ozone

Your AC may be smelling like vinegar because it releases an unseen pollutant, ozone, into your home. ACs that use electric motors release ozone as electricity creates energy. Ozone has an intense burning wire-like smell, which is unpleasant to your nostrils. 

If your AC produces large amounts of ozone, you may find the smell more of a pungent vinegar odor. As we know that too much of anything is poisonous; too much ozone releases harmful toxins in the air. It may put you and your house occupants at risk of respiratory, cardiovascular, and nervous system diseases. 

Faulty Air Filter

If your AC has a faulty or malfunctioned air filter, it may explain why your AC smells like vinegar. The air filter removes pollutants and prevents them from circulating in your home. 

A faulty air filter in your AC system will allow the expulsion of mold and other toxins through your air conditioner. These expelled elements can have a vinegar-like smell creating discomfort in your spaces. 

Blocked Condensation Pan

The condensation pan of your AC is essential as it helps to drain the condensation drips. What happens when your condensation pan blocks? While it is rare in your home, it can happen. 

Dust particles and other materials from your home’s surroundings can clog the condensation pan. This prevents your condensation pan from draining condensation drips. Your AC then becomes a habitable environment for the growth of mold and other bacteria, which makes your AC smell like vinegar. 

By now, you already understand how harmful this mold buildup is harmful to your health. You, therefore, need to clean the condensation pan regularly by running it under hot water. 

How to Get Rid of Vinegar Smell Out of Air Conditioners

You don’t want to endanger your health and that of your home’s occupants, even with the foul smell from your air conditioner. You can try these solutions to get the vinegar smell out of your air conditioner. 

Discover the Underlying Cause

It would help if you discovered the cause of the smell first. While it is most likely the AC causing the smell when you turn it on, do not overrule the possibility of the smell coming from other places.

I recommend that you track your AC smell. If the vinegar smell lingers when the AC is on, and it goes away when you turn it off, then it means that your AC is the underlying cause of the smell.

What’s Causing the Smell

Next, you need to find out what is causing the smell. You already know that a faulty air filter, clogged condensation pan, mold buildup, and ozone emission can all cause your home AC to smell like vinegar. 

The air filter captures all the toxins and dust to allow you to breathe clean air. As such, your faulty air filter may be the culprit causing the smell. It would be best to replace it to eliminate the vinegar odor from your home AC. 

Talk to an HVAC Technician

Sometimes, you may not have all the solutions, and it is okay. Perhaps you have replaced your air filter, and the vinegar odor still lingers in your home; what should you do? I recommend getting help by talking to an HVAC technician. 

An HVAC technician will be able to unmask any problematic issues. They can replace the air filter and still thoroughly inspect your AC system to prevent the vinegar odor problem from reappearing. 

How to Fix the Issue

If you are looking to fix the issue without calling the HVAC technician, I recommend investing in AC cleaning chemicals. AC cleaning chemicals get rid of all the dirt and grime accumulated in your AC. The cleaning products have enzymes that will clear AC air filters, eliminate the vinegar odor, and allow clean air circulation around your home. 

Other Home Air Conditioner Smells and Their Meanings

You have finally rid your home of the vinegar odor, and you probably think you are back to a comfortable home. Soon after, you notice another smell haunting your home, but this time it is different from the vinegar odor. You may experience; 

Air Conditioner Smells Musty

If your AC smells musty, you may be having clogged ductwork. Your condensation pan may be working slowly to drain off the droplets, providing a warm and moist environment for mold buildup. Your AC will then have a clogged air filter and condensation pan, releasing a musty smell into your home once you turn it on. 

Freon Leak Smell

Does your AC produce chloroform but sweet smell when you turn it on? If yes, then you may be experiencing a Freon leak smell. 

Freon is the chlorofluorocarbon that removes heat from the atmosphere to transfer it outside your home and maintain cool temperatures. It travels through closed copper coils in your AC. If these closed copper coils crack, they can result in Freon leakage causing your AC to emit the Freon-like smell. 

Deep inhalation of Freon can cut off vital oxygen to the cells and lungs. You should call your HVAC technician immediately you sense the Freon-like smell. The technician can use a Freon leak detector to identify and fix it before Freon reaches toxic levels. 

AC Smells Like Gas

If your AC smells like gas, then you probably have a gas leak. Long hours of exposure to an AC smelling like gas reduces oxygen levels in the blood, and you may lose consciousness. You need to immediately open the air outlets in your home, evacuate, and call the gas company. 

Air Conditioner Smells Like Chemicals

Your AC smells like chemicals due to a couple of reasons. If you have open or improperly sealed chemical containers near the AC intake, the smell may circulate to the rest of the house once the AC picks it up. 

The fluids that your AC uses to operate effectively may also cause it to smell like chemicals when it malfunctions. It can emit formaldehyde, paint thinner, or a chemical-like smell, telling you that it’s time you called an HVAC technician to look into the issue.

Your AC can also smell like chemicals if you have recently done some ductwork. Excellent duct installation will require some glue, which smells like chemicals as it dries off. 

Air Conditioner Smells Like Paint Thinner

If your AC smells like paint thinner, it most likely has a malfunction. The fluids used within the system can emit a paint thinner-like smell upon malfunction. You should call your HVAC technician to assess the AC system before use or to diagnose the system. 

Air Conditioner Smells Like Rotten Eggs

Your AC smells like rotten eggs, gross, right? As long as there are no rotten eggs in your home, the rotten eggs smell may signify a gas leak. You should open your windows, evacuate the house, and call the gas company to address the issue immediately. 

If the gas company does not find an issue, there is a dead animal in the AC unit. You can contact an HVAC professional to help remove the dead animal.

Burnt Smell from AC

A burnt smell from AC signifies a mechanical problem with the wiring, compressor, or fan motors. If you have not used your AC recently, you may notice a burnt smell or electrical wire odor the first few times you use it. Do not panic if the smell dissipates after approximately half an hour. It is expected as the AC may be burning off dust. 

You should only engage the services of an HVAC professional if the burnt smell persists. If you are a DIY fan, you can also do a DIY AC repair if you notice a burnt smell from AC. However, I have to warn you that DIY repairs can cause severe injuries, especially if you have limited electrical knowledge.

Air Conditioner Smells Sour

If you notice a sour smell from your AC, your condensation removal system may be having a problem. Poor condensation drainage can cause sour-smelling bacteria to grow in your AC system. You can change your air filters and clean the condensation pan if you notice your AC smells sour.

How to Get Rid of Smell from Air Conditioner

After identifying foul smells in your air conditioner, you want to get back the pleasant odor in your home. So, how do you remove smells from your air conditioner?

Flushing the Air Conditioner’s Drain Line

I recommend flushing your drain line, otherwise known as the condensation line. If your condensation line is clogged, you will soon get a musty smell in your home. 

Start by switching off the AC unit when flushing, then head out to locate the T-shaped cap on the drain line. Remove the T-shaped cap, check for blockage and clean it using vinegar.

A wet/dry vacuum cleaner would also flush the AC’s drain line. You can place the hose over the line and turn on your vacuum cleaner to suck out any blockage.

Cleaning Out the Air Conditioner’s Drain Pan 

A dirty drain line of an AC smelling bad also screams a dirty drain pan. So, it would be best if you also cleaned your AC’s drain pan. How? 

Well, this is simple. First, wash the dirty drain pan with warm soapy water. Second, rinse the now halfway clean drain pan with vinegar or bleach to remove mold remainders. You can then air the drain pan, allow it to dry, and put it back in its place.

Preventive maintenance can also go a long way in keeping your drain pan clear. You can put a ¼ cup of household vinegar into the drain pan twice a month.

Allow the household vinegar to sit in the drain pan for 30-45 minutes, then rinse it off with warm water. The mold or bacteria will die out, leaving you with a pleasant odor in your home.

Replace the Air Filter

If your AC air filter is the culprit, then you will need to replace it to enjoy a pleasant odor in your home again. Replacing the air filter is an activity you can do yourself, but if you are not sure, you can seek the help of an HVAC professional.

If your AC has a disposable filter, you need to get rid of the existing one and put on a new one, and your home will be back to its pleasant odor. 

If your AC system uses a reusable filter, you need to remove it and clean it with warm soapy water. You can rinse it with diluted bleach or vinegar to kill any remaining mold or bacteria.

Professionally Cleaning the Ductwork

Sometimes, getting rid of your AC smells can turn into a nightmare. If your AC has substantial mold and dust buildup, the ducts have rodents and insects you are probably worried about.

Do not panic, as professionally cleaning the ductwork will come in handy. It involves cleaning all the heating and cooling components of your AC system.

Professional ductwork cleaners use specialized tools to dislodge the dirt and chemical biocides to eliminate microbiological contaminants. I recommend engaging the services of professional duct cleaning companies to clean your AC ductwork professionally.

You can contact the National Air Duct Cleaners Association (NADCA) to get information on the best cleaners. You should also know that EPA does not recommend air duct cleaning unless on an as-needed basis.

Be Sure to Take Precautions Before Doing a Diy

If you are a DIY fan, then you are probably a risk-taker. You know that you can fix almost everything with just a few guidelines. However, it would help if you took a couple of precautions before doing a DIY to fix the horrible smell from your AC system.

When the AC smell hits, you may be tempted to DIY and mask the smell with an air purifier or freshener. It is a wrong move. Immediately you notice an unpleasant AC odor; I recommend finding the underlying cause. If you delay repair work, you will end up with greater pains than gains. You may have to replace more parts or purchase an entire AC unit as the damage has worsened. 

If you have limited electrical knowledge, do not attempt to do AC repairs yourself. Even when you have watched what your HVAC professional did last time, I still recommend getting a professional to work for you or with you. Your AC has many electrical components, and one wrong move can cause a fatal electrical shock, which you do not want.

For the less engaging activities that may not require electrical expertise, ensure that you go through the AC maintenance and operating manuals. Here, you will find information on removing or installing various components. You will also get information on the right tools to use for your DIY on the AC, preventing any incidences.

Most importantly, always ensure that you turn off the main power supply of your AC and you put on the appropriate personal protective equipment (PPE) before attempting a DIY.

How to Clean an Air Conditioner

Whether cleaning an outdoor or indoor unit, the first step should always be deactivating the power supply for your safety.

  • Start by opening up the AC unit if you begin with your indoor unit. Next, use a soft brush to remove dust and other particles from the evaporator coils. If you cannot reach some areas by hand, you can spray a no-rinse coil cleaner to your evaporator coil, which will drain out all the dust and dirt particles.
  • Use warm and soapy water to clean the drain pan, followed by bleach sanitization. If the bleach mixture flows speedily down the drain line, you do not need to clean the drain pan, as it is probably not clogged. If the bleach flow is sluggish, use a vacuum hose to blow off the clogging material. Lastly, reattach the access panel complete with the screws. 
  • You can start by removing debris on the air conditioner either by hand or using a vacuum hose to blow the debris out for the outdoor unit. 
  • Next, you should clean the AC coils and fins. It would be best if you had a diluted coil cleaning solution. Put this solution in your pump sprayer, spray it on the coils and fins, and allow it to foam up. After a few minutes, you can rinse it off.  Now, you can proceed to clear two feet around the area of the AC unit. 
  • For your air filter, you can vacuum to remove dirt and debris. You can also soak it up in soapy room temperature water for 15-20 minutes and allow it to dry, and then fix it back to your AC system.