Have you ever visited a home where the air just smelled…stale? Maybe you have a room or two in your own home where the air isn’t as fresh as you’d like.
Without optimal air flow through your home, dirty, greasy or smelly air can collect and become stagnant. Many homes are equipped with exhaust fans – like your bathroom fan or range hood to pull stale air out of the house and fresh air in.
These usually work fine when the fan is running – but problems can arise when the fan is turned off. You see, there will always be some air flow through your home even when the fans are off. For healthy indoor air the flow direction should always be in the direction the ventilation system was designed for. If there’s nothing to prevent it, air can come back the wrong way through the exhaust fan opening. This is called a backdraft, and it can cause stale air that should be flowing out to back up and collect where it’s not wanted.
Fortunately, the problem is easily solved with an unglamorous but very effective little device called a backdraft damper. It’s basically a one-way valve that keeps the air going the right way.
Backdraft dampers, such as the Fantech Backdraft Damper or the Cape Backdraft Damper by Tamarack, are usually easy to install and come in various sizes to fit your ductwork. Use them to facilitate air flow, equalize pressure between different parts of a building, and in chimney, furnace, attic and stove vents to release hot air and prevent outside air from backing up.
Which coriolis direction will rising hot indoor air spin inside a room?