Imagine you come home after a long, hot, humid day. You take your boots off, loosen your tie, and turn your AC on (you wouldn’t be doing the last step if you had the Cielo Breez Plus), but smell something awry.
A bad stench fills your room, forcing you to turn your AC off.
You wonder, why on Earth does my air conditioner smell bad? Does this mean more savings going down the drain?
In this post, we’ll go over some of the common reasons why you may have a stench erupting from your air conditioner. The smell could be of anything, such as a wet sock-like odor, something burning, or even a smoky smell.
Let’s go over some possible smells that AC owners are likely to experience and find out the reasons for their occurrence, along with their solutions.
Types of Air Conditioner Smells, Possible Causes and What You Can Do
One of the most serious things that homeowners have to deal with is bad AC smells. But the problem is that you won’t know if the smell is coming from your unit, what type of smell indicates what issue, or what does Freon smell like. And to deal with the problem, you need to learn about it first!
We’ve explained in detail about every kind of smell that you can experience if you own an air conditioner. So let’s take a look:
1. Air Conditioner Smells Like a Car’s Exhaust?
An air conditioner does not run on an internal combustion engine. So, there is no reason why your air conditioner should smell like running car exhaust. However, your air conditioner does make use of some fluids, and when heated, they can smell like exhaust fumes.
A smell from an AC such as this most likely means there is a leak in your refrigerant line. A refrigerant is a cooling agent inside your aircon, and a leak can impact the performance of your air conditioning unit. Moreover, it releases chemicals into the air and thus can be hazardous for the environment.
Freon, a chlorofluorocarbon, is a commonly used refrigerant used in your air conditioners, although it is being slowly phased out. Freon absorbs heat from the indoor air, which is released outside. But it can be really dangerous for the environment. Therefore, you should always be careful if you suspect there is a Freon leak.
Whenever you’ve read something regarding a refrigerant leak, you must’ve thought, what does Freon smell like?
A Freon leak would smell like sweet chloroform or, in simpler terms, just like your car’s coolant but with a sweetish odor. Even though it is an almost odorless gas, you can still detect the smell. But Freon, being heavier than air, does not linger around in the air for long, and drops down to floor level pretty quickly.
If your AC is emitting a chemical-like smell, you should get it checked promptly by a professional. A Freon leak can be dangerous, and a certified HVAC specialist will repair it in no time.
In the meantime, crack open the windows and make sure your home is ventilated. This will not only keep the smell out but also prevent any hazardous effects from the chemical leak.
2. AC Smells Like Something Is on Fire?
There are a lot of electrical components within your air conditioning unit—circuit boards, power wires, fans, and compressors, etc.
If your AC smells like burning gunpowder or plastic, it probably means any one, or even multiple of these components are in fact, burning. In this case, immediately turn your air conditioner off and consult your local professional for a solution.
Do not attempt to do a DIY with this sort of a problem; it can be dangerous.
Another more common reason for such an air conditioner smell is that dust can settle within your unit after a long period of inactivity. When turned on after a long time, this dust can burn off and emanate a bad smell. This is only temporary and is nothing to be too concerned about.
Though if the smell remains, the AC starts to malfunction or the smell is highly pungent, you must turn off your unit and give your local HVAC expert a call right away.
3. Are You Smelling Rotten Eggs From Your AC?
A foul or rotten air conditioner smell is usually the result of dead rodents or critters stuck in the AC. This is a characteristic and distinct smell that you surely cannot mistake for anything else.
Birds and insects can nest or take refuge in your ductwork and, unfortunately, get trapped in the equipment.
With time, these dying animals emit unpleasant smells. As soon as you turn your air conditioner on, it can discharge a foul smell into your home. Dying or stuck animals can also damage different components within your system.
If you have a ductless/central air conditioning system, lizards and other critters can sometimes go into your indoor unit and make for an unpleasant experience.
It’s best to always pest-proof your unit to avoid such a nasty scenario and having your AC smell like a carcass. You can always call a technician to help remove the dead animal, or you can fix this issue yourself!
You will need to locate the exact duct from where the stench is erupting, use a screw driver to remove the cover, and then carefully remove the carcass. It can be tricky if the dead animal is not in sight. Keep a torch in quick reach. Once removed, gently wipe the area clean and make sure it is dry. It is recommended to have your ductwork checked to ensure nothing is damaged and seal any entry points.
4. Do You Smell Gas and Feel Like There’s a Skunk in the House?
This air conditioner smell is the most alarming one on our list. More often than not, this indicates leakage of gas within the system, specifically, Methyl Mercaptan.
Natural gas on its own has no smell, but utilities and gas distributors put in Methyl Mercaptan to provide a distinctive odor to it. This ensures immediate detection to prevent any serious harm that can occur from gas leakage.
If your AC smells a lot like skunk spray, you won’t be mistaken. This means that gas is leaking and getting into your ductwork. At the first sign of such a smell, immediately turn off your gas supply. As a second step, contact your utility, who will detect the source and repair the problem.
5. Getting a Moldy or Musty AC Smell?
A stale and dingy smell is by far the most common and foul smell experienced from ACs. If your AC smells musty, the general cause is the accumulation of water in the drain pan or drip lines (or ducts in case of ducted systems), which can cause fungus or mildew to grow.
In case of a leakage, you might even get visible signs in your indoor ductless unit, such as water dripping down your wall.
Another reason for such a smell can be dirty filters. If you live in a hot and humid climate and turn your AC on after a long period of time, moisture can accumulate in your filters.
You will need to contact a professional and get your AC’s lines and ducts thoroughly cleaned. This will only remove the unpleasant smell. In case of a leakage, the source will also need to be fixed to prevent further problems.
6. Air Conditioner Smells Like Cigarette Smoke?
If you smoke at home, then there are chances that your AC will eventually end up smelling like stale cigarette smoke. This unpleasant smell can cause allergic reactions and headaches.
Your evaporator coil and filter absorb the odor from cigarette smoke. As a result, when you turn on the air conditioner, the embedded tobacco particles are knocked loose and sent back into your home through the AC’s vents, creating an unpleasant atmosphere.
Like all other problems, this problem has a simple solution. To eliminate the old tobacco smoke smell from your AC vents, change your air filter once every 30 to 60 days and clean your AC regularly. You can also start smoking outdoors.
Be Sure to Take Precautions Before Doing a DIY
There are a couple of things to keep in mind while we are at it.
Never try to do AC repairs by yourself. Always call a professional to do the job for you. Electrical components and water do not mix well, and there is a high chance of electric shock. You would be making a wise choice not to experiment at such a time.
If you do feel qualified enough to do a DIY, be sure you have thoroughly gone over your air conditioner’s maintenance and operating manuals. Then collect the right set of tools for the job. Finally, turn off the main power supply to your AC and have proper personal protective equipment (PPE) at hand.
Moreover, do not try to mask the bad smell using an air purifier or freshener. It will only make things worse. Delaying proper repair work will only damage your AC more than it already is and perhaps lead to you buying a whole new unit altogether.
Why my air conditioner smells bad? Hopefully, now you have the answer to the question!
Be it ducted or ductless air conditioning, all the factors above make for an unpleasant experience. So, the next time you come home and experience an unpleasant odor, you know exactly what it could be and what you need to do to fix the problem.