We've had thick smoke outside our home for several days now due to the fires on the west coast. We're doing what we can to filter the inside air and keep excess outside air from coming in (covered fresh air intakes, the dryer vent, etc).
You usually can't smell any smoke indoors even though it smells awful outside all day. However, every morning and every evening the smoke smell comes in for a few hours. I'm curious what causes it.
My best guess is that the air pressure outside increases during those times and that causes the exchange of air to increase. But that's just a wild guess.
Can anyone shed on light on what's happening?
Best Answer
The most common issue when you have make up air on a hvac systems is when the kitchen exhaust or bathroom exhaust fans are turned on they usually push 80-1000 cuft and that air is sucked in vis the central heat or air ductwork. If an older home is is pulled in through all kinds of leaky air spaces.
The most noticed time when the bathrooms and kitchen exhaust fans are running pushing house air out and bringing fresh / Smokey air in.