No, you should not rely on your air conditioner to filter out wildfire smoke. It could be helpful after the wildfire has cleared the area, but it can also be a liability if the wildfire is still nearby. Here is what you need to know about how you should treat your air conditioner during and after wildfires.

do air conditioners filter out wildfire smoke?

During the Fire

If you know you’ll be close enough to a wildfire to be affected by the smoke, and you should evacuate the area. If that’s not possible, the CDC makes many recommendations about how to shelter in place. Chief among them is to attempt to seal the home and your lungs from the smoke. There are several ways to do this, and it is best to do all of them. They include:

  • Use a respirator
  • Stay in one room you can seal off
  • Use a portable air filter in the room

You should also turn off all of the equipment in your home that circulates outdoor air. This includes your air conditioner. Instead of filtering out the air, your air conditioner could pull smoke into your home.

After the Fire

When you return after evacuation or start to explore other rooms in your home once the wildfire has passed, you will likely find that your home has some amount of wildfire smoke in it. It is wise to attempt to clear out the smoke to reduce its impact on your health.

However, air conditioners are not the tool to use to do this. Air conditioner filters are a very high MERV rating (which means they are poor at filtering out small particles as higher numbers are worse on the MERV scale). They are intended to protect the unit itself from dust and hairs and not actually filter the air in your home.

When you want to filter out wildfire smoke, you need a powerful filter and one that will move through a high volume of air quickly. According to the EPA, HEPA filters can be suitable for this purpose and can reduce the concentration of particles in your air by as much as 85%.

In order to be this effective, you may have to change the filters very frequently. It can help to have professional advice from your HVAC technician to ensure both that your air purifier can target small enough molecules to pick up smoke and also to let you know when the filters need to be changed.

It is also a wise idea to use a vacuum that has a HEPA filter. These can gather up the smoke particles that have settled on surfaces to prevent them from being kicked back up into the air. However, using a vacuum without a HEPA filter will simply return the smoke particles to the air–so don’t do that.

Learn More About Wildfire Smoke & Indoor Air Quality

The EPA’s guide to wildfires and indoor air quality is a great place to start. 

If you need more advice about your air conditioner or about your air quality after a wildfire, it is wise to reach out to our professional HVAC team that can help you with air conditioning repair in Livermore and beyond.