Do Dehumidifiers Emit Carbon Monoxide?

Dehumidifiers are great appliances that help to keep the air you breathe safe and comfortable.

These appliances effectively wring out the moisture found in the air that makes it humid, reducing the chance of mold or other harmful particles.

If you own a dehumidifier, you may notice it’s been setting off your carbon monoxide detector – but why?

Dehumidifiers are powered with electricity and cannot emit carbon monoxide. However, since dehumidifiers are designed to take and release air, it’s important to place them away from gas-powered machines to avoid recirculating fumes from these machines.

Stay aware of your surroundings when setting up a dehumidifier. You should place a dehumidifier in a location where it will collect a lot of airflow.

It’s common to place your dehumidifier in a basement, but make sure to keep it away from any heaters or gas-powered machines as it may absorb the exhaust they emit.

Like all other dehumidifiers, our dehumidifier doesn’t emit carbon monoxide but as it acts much like a fan, we keep it away from our gas-powered appliances and anything that could produce carbon monoxide, such as the fireplace.

Keep a dehumidifier away from anything else in your home that could produce carbon monoxide

Keep reading to learn more about dehumidifiers and carbon monoxide emissions.

Dehumidifiers Cannot Emit Carbon Monoxide

If carbon monoxide emission is a dealbreaker when it comes to purchasing a dehumidifier, then you’re in luck.

It’s physically impossible for dehumidifiers to emit carbon monoxide from their own doing.

They are electrical machines and cannot produce carbon monoxide like gas-powered devices can. You can sleep safely with a dehumidifier in your room knowing full well it will not harm you in this way.

  • Dehumidifiers are designed to absorb air that passes through them, so make sure it’s not picking up exhaust or any other type of discharge from a machine close by.
  • Carbon monoxide detectors may be going off because the house or space is not properly ventilated, causing contaminant buildup in the air. In addition, the chemical carbon monoxide (CO) tends to bond with other ions and particles,  making CO dangerous to your body.
  • The air could simply just be too humid, be sure to adjust the settings on your dehumidifier and make sure that it is pulling enough moisture out of the air to not cause CO sensors to go off due to density in the air.

If your carbon monoxide (CO) detector is going off around your dehumidifier, there’s no real reason to stress if you suspect that it is a malfunction of some sort.

It’s very unlikely that a dehumidifier will set off a carbon monoxide alarm

As always, however, CO leaks are no joke and should be taken very seriously.

Use your judgment and do not hesitate to call a professional in the event that you do not know why it is going off.

It’s much better to be safe than sorry, CO poisoning can take lives.

Take Note Of The Location Of Your Dehumidifier

Now would probably be a good time to briefly describe how a dehumidifier works, as this may be why it is setting off your carbon monoxide sensor.

A dehumidifier will take the air that passes through it and “squeezes” out the moisture, contaminants, dust particles, mold, etc and release it as cool, thinner air to make it easier to breathe.

These are great for basements, laundry rooms, garages, or anywhere else.

Your dehumidifier could, albeit rarely, be pulling air that was discharged from a gas furnace for example.

The location of your dehumidifier matters here because the exhaust taken in is the same that it is pushing out. So, if it is taking in exhaust from a machine that operates via combustion then it will go through the dehumidifier and possibly be released back out into a living space.

This event can trick your carbon monoxide detector into thinking that it is reading CO, but is in fact just recognizing dirty air.

Carbon monoxide by nature tends to build up over time in the presence of combustion fumes.

It’s the reason why you have always been told not to leave your car running in your garage, these fumes build up and eventually take over your bloodstream.

If you think it is CO buildup, call a professional immediately.

The manual to our dehumidifier states:

Do not use dehumidifiers where flammable gases or VOC [volatile organic compounds] can be released or accumulate.’


Ventilation Will Clear The Air

Your dehumidifier may be acting as intended and it may not be within close proximity of any fuel-based machinery, but your carbon monoxide sensor is still going off.

This could be a by-product of not having a room that is properly ventilated.

First of all, any room that has machines that operate through combustion should be ventilated thoroughly.

Your CO detector could be going off because of buildup in the air from everything contaminating it or it could just be humid. It’s not worth second-guessing, call a professional and get your room ventilated properly.

Again, your dehumidifier will not cause your CO sensor to sound the alarm. It will be the air that you designated your dehumidifier to regulate.

A dehumidifier is not a form of ventilation and should never be considered as such.

It pushes out the same here it takes in and works with the preexisting airflow in the room. Ventilation will actually cycle new air in while it pushes old air out. If you are not bringing new air in, that is the issue.

Windows and doors should ideally be closed when using a dehumidifier but if there’s a combustion appliance nearby then it’s more important to have the windows ajar for proper ventilation.

Keeping windows closed is more efficient for a dehumidifier but ventilation is also important when using gas or carbon monoxide-producing appliances

The Air May Be Too Humid

As mentioned earlier in this article, dehumidifiers work by disposing of the moisture in the air. Therefore, you can use the settings on your dehumidifier to choose how much humidity you want to take out.

Your carbon monoxide detector might be recognizing that there is a buildup in the air and not any carbon monoxide at all.

Carbon monoxide poisoning happens over time, which is one of the many reasons that make it dangerous for humans. It slowly happens over time because it has to build up, making the air thick and humid. This could be a false alarm or it could be a real problem.

The first thing you will want to take inventory of is whether or not there’s any type of gas leak or combustion fume of any sort coming from somewhere in your home.

This could be a car running in a garage, a furnace that is not properly ventilated, or an open flame such as a charcoal grill in the kitchen. If there is nothing like that happening in your general vicinity indoors then it is likely not a problem and can be fixed easily.

What you will want to do is check the display on your dehumidifier and check to see what the humidity threshold or percentage is set to. If the humidity percentage is set to 70% for example, then it is too high and needs to be turned down.

Adjust this on the fly and let the machine run its course and you should not have any problems. If you are not positive about what the problem is then call a professional immediately to fix it.

Can A Dehumidifier Set Off A Carbon Monoxide Detector?

Dehumidifiers cannot emit carbon monoxide, and therefore cannot directly set off a carbon monoxide detector.

Carbon monoxide is called “the silent killer” for a reason and should be taken extremely seriously if you suspect that there is carbon monoxide buildup in your home.

The biggest takeaway from this article should be that other factors contribute to why your CO detector is going off. Still, it rarely has anything to do with your dehumidifier.

Further Reading

Can A Dehumidifier Act As An Air Purifier?

Can A Dehumidifier Eliminate Odor?

Do Dehumidifiers Have Filters?