Buzz
If you reside in a region impacted by wildfire smoke—whether it's the current haze enveloping the east coast or the recurring fire seasons in the west—you're probably staying indoors more often to escape the unhealthy outdoor air. Key strategies for safeguarding indoor air quality involve shutting doors and windows and using an air purifier (which can be a DIY project). Additionally, the CDC advises closing your air conditioner's fresh air intake. But how can you determine if your home has one, and what steps are needed to deactivate it?
Defining a fresh air intake system
A fresh air intake serves the purpose you might guess: It draws in outdoor air to refresh your home's interior. This process not only enhances indoor air quality by minimizing dust and preventing the accumulation of pollutants—it also ensures your furnace and HVAC system operate efficiently and can help lower energy expenses.
However, when outdoor air quality deteriorates, your fresh air intake might cause more harm than benefit.
Steps to find and shut off fresh air intake vents
Many modern homes are equipped with one or more fresh air intakes to meet building regulations. These vents are typically either metal hoods or plastic pipes situated outside, near the ground level of your house, though they can also be found on the roof or in the attic. Additionally, you might spot grilled intake vents near or behind your furnace or other gas-powered appliances.
To identify whether a vent is for air intake (as opposed to expelling air), place your hand beneath it while the furnace is operating. If you sense air being drawn in, that confirms it. Air intakes are also equipped with screens, whereas exhaust vents have flaps.
In most instances, shutting an air intake is as straightforward as adjusting the damper to the closed position by turning the handle, knob, or switching off the fan. Alternatively, if your HVAC system features a “recirculate” mode, activate that setting.
