Informational Guide

Why Does My Air Purifier Smell Bad? (Causes & Solution)

by Josh M

Does your air purifier smell bad? Unfortunately, this is a common problem with air purifiers, and it is pretty frustrating and embarrassing at the same time.

Fortunately, we have several reasons for the unpleasant smell and the possible solutions. So, read along; we got you covered.

Off-Gassing Filters

Many air purifiers come with activated carbon filters that help remove harmful gasses and odors from the air. However, these filters can sometimes cause a problem known as “off-gassing.”

The chemicals cause the odor in the filter to be released into the air.

Poor Room Ventilation

If your air purifier smells musty, it may be because of poor room ventilation. When rooms are not well ventilated, air can become stagnant and smell.

In addition to causing unpleasant odors, poor ventilation can also lead to health problems. Stagnant air can contain high dust, pollen, and other airborne contaminants.

Filters With A New Appliance Smell

You’re not alone if you’ve ever noticed that new air filters have a strong smell. Many people are surprised to find that their new air purifier emits an unpleasant odor when they first turn it on.

While the smell can be off-putting, it’s a good sign that the cleaner is working correctly. The new filter smell is caused by the chemicals used in the manufacturing process, and it should dissipate within a few hours of use.

Ozone Production

One of the most common questions we get is why is it that air filters smell? You know the one – it’s that faint but unmistakable odor that air purifiers emit when they’re first turned on. But what exactly is that smell, and is it harmful?

The air filter smell is ozone, a gas naturally present in the air we breathe. Ozone is produced when oxygen molecules are exposed to high levels of electrical energy, and air purifiers use this process to clean the air.

While ozone is safe in small amounts, too much exposure can irritate the lungs and cause shortness of breath.

Related ArticleAre Ionic Air Purifiers Safe?

Bacteria, Yeast, and Mold Growth

If your air purifier has started to emit a sour smell, it may be due to bacteria, yeast, or mold growth. While these organisms are generally harmless in small amounts, they can cause the air purifier to smell bad if in large quantities.

The most likely cause of bacteria, yeast, or mold growth is stagnant water in the air purifier’s reservoir. When water sits for too long, it becomes a breeding ground for these organisms, causing them to multiply in large amounts.

Related ArticleDo Air Purifiers Help With Mold?

Saturated Activated Carbon Filters

Saturated activated carbon filters are one of the most common air purifier filters. They work by trapping airborne contaminants in their pores as air passes through the filter.

Over time, the pores in the carbon filter become filled with contaminants, reducing its ability to clean the air. As a result, air purifiers equipped with carbon filters may produce stale or bad smells.

Off-gassing Plastics Around The Air Purifier

Perhaps you’ve noticed that your air purifier smells bad, and you’re wondering what the cause might be. More than likely, it’s because of off-gassing plastics around the air purifier.

Off-gassing occurs when chemicals from the plastic are released into the air, and these chemicals can cause a strong, unpleasant odor. In addition, they can also be harmful to your health if inhaled for prolonged periods.

Faulty UV Light Filter Bulbs

If your air purifier has been smelling bad lately, it could be due to faulty UV light filter bulbs. These bulbs are responsible for killing bacteria and viruses.

When they stop working correctly, they can release dangerous toxins. This poses a health risk, but it can also make your home smell unpleasant.

Related ArticleDo UV Air Purifier Work?

An Electrical Fault

If your air purifier smells like it’s burning, there’s probably an electrical fault somewhere in the unit. This is a severe problem that needs to be fixed immediately, as it could lead to a fire.

The first thing you should do is unplug the air purifier and check for any visible signs of damage. If you see anything that looks damaged or melted, it’s best to replace the entire unit.

How To Get Rid Of Bad Smell In The Air Purifier?

Depending on the underlying problem, it is possible to get rid of the cause of the foul smell emitted by the air purifier.

Off-Gassing Filters

The good news is that the off-gassing filter smell will disappear after a few hours. To get rid of it sooner, you can try running the air purifier on a lower setting or using a HEPA filter.

After several use cycles, the smell will go away from off-gassing plastics around the air purifier, and there is no need to worry.

Poor Room Ventilation

To get rid of the foul smell in your air purifier in the case of poor ventilation, you will need to improve air circulation in your room.

Start by opening a window or door to let fresh air into the room. You can also turn on a fan to help circulate the atmosphere much faster.

Filters With A New Appliance Smell

Often, the smell of a new filter goes away within a few minutes of turning on the air purifier. However, in some cases, the smell doesn’t go away, and the best solution, in this case, is to choose a HEPA filter.

These filters are designed to trap dust, pollen, and other airborne particles, and they’re incredibly effective at removing smells.

Ozone Production

Luckily, you can do a few things to eliminate the ozone production gas smell. First, make sure that your ozone air purifier is properly ventilated. Second, change the filter regularly.

Third, avoid using ozone-producing air fresheners. Fourth, consider using an air purifier with negative ion technology instead of ozone technology.

Bacteria, Yeast, and Mold Growth

Start by emptying the water reservoir and cleaning it with a mild soap. If there is any build-up of dirt or mold, you may need to use a more potent cleanser. Be sure to rinse the reservoir thoroughly before adding fresh water.

Next, clean the filter according to the manufacturer’s instructions. If the filter is filthy, you may need to replace it.

Finally, disinfect the entire unit by running a cycle with vinegar water. To do this, mix one-part vinegar with three parts of water and pour it into the water reservoir. Run the air purifier for one cycle, then empty and rinse the reservoir.

Saturated Activated Carbon Filters

If your carbon filter smells weird, there are a few things you can do to freshen it up. First, try soaking the filter in a mixture of water and vinegar for 24 hours.

This will help break down any build-up on the filter and neutralize unpleasant odors. If you have an air purifier with multiple carbon filters, be sure to rotate them out regularly so that each has a chance to dry completely between uses.

Faulty UV Light Filter Bulbs

A lingering smell, at times, is caused by faulty UV light filters, which can allow bacteria and mold to build upon the bulb and in the entire system. You’ll need to replace the air purifier’s UV light filter bulbs to fix this.

An Electrical Fault

If your air purifier smells like it’s burning, there’s probably an electrical fault somewhere in the unit. This can be a severe problem, so it’s essential to take action immediately.

First, unplug the air purifier from the power outlet. Then, open up the unit and inspect all of the wirings. If you see any frayed or exposed wires, carefully tape them up or replace them entirely.

Once you’ve repaired any faulty wiring, test the air purifier by plugging it back in and running it for a few minutes. If the burning smell persists, there may be another issue at play. Try cleaning all of the air purifier’s filters to see if that makes a difference. If not, you may need to take the unit to a professional for repairs.

Why Is My Air Purifier Smell Bad? (Explained for Different Brands)


If your Honeywell air purifier smells like burning, it could be because it is overheating or the fan is restricted, hence inadequate airflow.

Your Honeywell air purifier smells like plastic, and you probably wonder what could be the issue. This can result from the outer plastics off-gassing due to its first usage. Another reason could be due to overheating.


Suppose your Dyson air purifier smells like vinegar, then this can be a result of vinegar being used to clean the filters. Please take out the filter, rinse off with a lot of water, and then dry it before reinstalling it.


Levoit air purifier burning smell. If you have a Levoit air purifier, you may have noticed a burning smell coming from the unit.

This is normal, and you should not be concerned. The smell is caused by the heating of the filter, which is necessary for the purifier to work effectively.

The smell will dissipate shortly. If it doesn’t, unplug it and assess.


If your Holmes air purifier gives off an electrical smell, it could be due to different issues.

First, ensure that the unit is properly plugged in and that the outlet is not overloaded. Then, if the problem persists, check the filter to see if it needs to be replaced.

It’s also possible that the motor is overheating; if this is the case, unplug the unit and let it cool down for a few minutes before restarting it. If the smell continues, contact Holmes customer service for further assistance.


Oreck air purifier smells like ozone. If you have an Oreck air purifier, you may have noticed that it sometimes emits a smell that resembles ozone.

While this may be concerning, it is perfectly normal and nothing to worry about. The reason your air purifier smells like ozone is that it uses ozone to clean the air.

pet air purifier

People Also Ask (FAQ)

Frequently asked questions related to air purifier smell.

Can a dirty air filter make your entire house smell?

The dirty air filter can cause the air purifier to smell bad, but it can also cause the air in your entire house to smell bad.

Why does my air purifier have a chemical smell?

Some air purifiers may produce a chemical smell when they are first turned on. This is usually due to the activation of the unit’s ozone generator, which makes ozone gas during the filtration process.

Do HEPA filters smell?

HEPA filters can indeed produce a slight odor. This is typically only when the filter is first installed or when it needs to be replaced.

Do Carbon filters smell?

The short answer is that some may smell when first used, but it should go away relatively quickly.


The key to making your air purifier smell good is quite simple. First, empty and clean the water reservoir, then clean or replace the filter. Next, disinfect the unit by running a cycle with vinegar water.

Finally, check for any electrical faults and repair or replace any damaged parts. If the problem persists, you may need to take the unit to a professional for repairs.

Last Updated on January 9, 2023

Josh M

My name is Josh and I am obsessed with the HVAC industry. I created this website to help HVAC techs of all levels get the best out of their heating & cooling systems. I have spent thousands of hours studying air conditioners, heaters and home air products so you can learn & buy with confidence. Learn more about the team here.