During Bay Area smoke events, the air inside a home can carry fine smoke particles unless it is filtered. Your heating and cooling system can help, if it has the right filter and is set up to use it.
During a Smoke Event
- Close windows and doors.
- Set the system fan to run continuously so air keeps passing through the filter.
- Avoid bringing in outdoor air; if you have a ventilator or fresh-air intake, follow its smoke setting or close it.
- Check the filter afterward and replace it if it is loaded with smoke.
Filters That Capture Smoke
Smoke particles are very small. Filters rated MERV 13 and higher capture a large share of them. Your system needs to move air through a filter that dense; deeper media filters do that with less restriction. Read what a MERV rating means.
Whole-House Filtration
A whole-house purifier or media filter cabinet cleans the air in every room the system reaches. We installed an IQAir purifier with a MERV 16 filter in a Kensington home alongside a new furnace and ventilator. See indoor air quality.
Frequently Asked Questions
Should I run my HVAC during wildfire smoke?
Yes, with windows closed, outdoor air intakes closed and a high-MERV filter installed, running the fan continuously keeps air moving through the filter.
Can a regular furnace filter stop smoke?
Basic fiberglass filters capture little smoke. MERV 13 or higher captures far more, in a system that can carry the airflow.