Does furnace take air from outside
Yes, some furnaces do take air from outside. This is known as a direct vent or sealed combustion system. In this type of system, the furnace has two pipes: one that brings in outside air for combustion and another that exhausts the combustion gases outside. This differs from a traditional furnace, which takes in air inside the home for combustion and then exhausts the gases through a chimney or flue.
Direct vent furnaces are more energy-efficient and safer than traditional furnaces because they prevent the possibility of back-drafting, which is when exhaust gases are pulled back into the home. They also improve indoor air quality by not using indoor air for combustion.
It’s important to note that not all furnaces are direct vents, so if you’re interested in this type of system, make sure to ask your HVAC technician about it.