Since the purpose of an air purifier is to remove pollutants and odors from the air, it’s not cool when they’re the cause of bad smells, right?
But there are times when your air purifier can smell like it’s burning, smell sour, or give off some other nasty scent.
We’ll detail the causes of various odors and what to do to solve the problem.
First, that burning smell.
Why Your Air Purifier Smells like It’s Burning
There are a few possible reasons for your air purifier letting off a burning smell.
- Electrical issues with the unit itself or the cord
- If it’s a model with a UV light, there could be issues with the bulb
Electrical issues with the unit or cord. Interestingly, electrical faults can cause your air purifier to smell of more than just burning or smoke—and we’ll get into that a bit more in a moment.
First, unplug your purifier as soon as you detect a burning smell and have factored out something else as the source.
Once you’ve disconnected the power, make sure the cord isn’t damaged. If it’s frayed, chewed, melting, or scorched, you’ve like determined the source of the smell.
It is possible to do a little DIY and replace a power cord, but you do need to be sure to use the same gauge cord and a similar connector.
After ruling out the cord and if you can open up the housing of the air purifier.
There may be an electrical issue inside that’s melting the plastic or overheating the housing.
This is where those other nasty odors come in.
If your purifier has a metal or plastic body, electrical issues cause a fishy or urine-like smell when the purifier is running.
If you see any proof of an electrical issue inside the housing, discontinue use immediately.
Issues with an ultraviolet (UV) bulb. Does your purifier use UV light to filter and sanitize pollutants?
There are two types of UV lights.
- UV-C (ultraviolet clarifying)
- UV-V (ultraviolet vacuum)
UV-C doesn’t omit ozone, but UV-V does. And ozone can smell light, a lightning strike, or static electricity—something like a burning or smokey smell to some.
This isn’t a fault. It’s just a byproduct of ozone being released.
However, a faulty bulb might cause an odor much like burning plastic.
Try replacing the bulb and see if that fixes the burning smell.
I mentioned that air purifiers can sometimes smell like air putrefiers instead of air purifiers.
Here are several other things that can and do produce foul smells.
Odors and Ozone Air Purifiers
Ozone air purifiers, also known as ozone generators, remove airborne pollutants and contaminants.
Ozone is a colorless, odorless gas that might produce other odors when released.
And some ozone generators can produce higher ozone levels than some states’ health standards.
But that’s another issue.
If you detect a chlorine-like smell coming from your air purifier, there’s a good chance it’s caused by ozone production.
As mentioned above, some people think ozone smells like something burning or smoky. However, you might think of something different when you smell it.
Here are several possibilities of what ozone may smell like to you.
- Bleach
- Burning plastic
- Chlorine
- Electricity
- Lightning
Musty, Sour, or Wet Dog Odors
These can smell pretty disgusting, so you don’t want your air purifier to add them.
So what’s the cause?
Does your air purifier use an activated carbon filter—even if used in conjunction with a HEPA filter, whether integrated or not?
Then that layer of activated carbon may be the culprit.
This layer of carbon is comprised of a large surface area that has significant absorption capacity.
That makes it excellent for filtering out dust and pollutants.
But it’s also one of the main reasons why an air purifier can smell sour, musty, or like a wet dog.
Here’s a little bit of science into what’s happening.
Activated carbon is made up of a variety of oxygen-containing groups like lactone groups and carboxyl groups.
These groups can fall away from the surface area and form acetic acid in a humid oxygen environment.
Acetic acid creates the taste and smell of sourness.
Once the activated carbon filter reaches a saturation point, the surface contains a large amount of absorbed formaldehyde, toluene, and other volatile organic compounds (VOCs).
All of which can produce a chemical reaction that then produces acetic acid.
So if you use an air purifier with activated carbon filters in any form, it’s essential to pay attention to humidity and change your filter regularly.
Offgassing Odors
First of all, what is offgassing?
During the manufacturing process of many types of goods, including plastics, organic chemicals, either in liquid or solid form, can become trapped.
If products are immediately packaged after production, these chemicals are further trapped, not to be released until you set your new item free in your home.
At that point, chemicals, gases, and volatile organic compounds (VOCs) are released into the air in vapor form.
Depending on where your air purifier is manufactured and by who, production standards may or may not apply, which can impact the level of offgassing.
Also, plastic is sensitive to heat, so you’re careful what plastics you put in your microwave.
Heat will not only melt certain plastics but also activate the release of some chemicals that could produce fumes.
So a burning plastic smell from your air purifier may result from offgassing.
Typically, air purifiers or any other product will eventually stop offgassing.
So if you continue smelling burning plastic long after the initial period of offgassing should last, you may have an electrical issue causing the smell.
A Lack of Sufficient Airflow May Cause Odors
Finally, a lack of airflow may be the cause of odors.
Your air purifier may smell like it’s burning or something else.
An air purifier should not be placed anywhere that doesn’t have significant indoor airflow, so there are no corners or tight spots behind furniture.
Pick the spot in your house or apartment with the highest air exchange level.
Dirty filters can also impact airflow, reducing efficiency and increasing your chances of smelling something nasty.
You can generally increase the efficiency of your air purifier by up to 20% if you put it in an optimal spot.
Putting it in a corner or behind furniture can reduce the overall air capacity by more than 50%.
Why Does My Air Purifier Smell Like Burning? Conclusion
An air purifier that smells like it’s burning—or any other foul odor—completely defeats the purpose of having an air purifier.
Clean, pure air rarely smells stinky.
The good news is there are identifiable reasons for an air purifier that smells.
And in many cases, it’s a simple fix.
The fix can be changing an air filter or UV bulb, placing your air purifier in a better position, or simply allowing it to sit and off-gas.
If your air purifier has an electrical problem and is scorching or melting something within the unit, immediately unplug it and either get it repaired or purchase a new one.