High Efficiency Furnace Venting Through Roof

What is vented is a residual corrosive condensate of water and carbon dioxide.

High efficiency furnace venting through roof. It uses a venting system to extract that heat before venting. This residual liquid is highly acidic. When the vent is withdrawing air from the house it expels the gas outside through the vent. If you notice water on the floor around your high efficiency furnace or water or rust stains within the cabinet your furnace is not draining properly.

If your furnace has an afue rating below 90 percent it will most likely have a flue pipe that goes up through your roof. Also known as the type b this vent is operating on the natural air convection. Example of high efficiency furnace venting on a roof 2. It s a high efficiency gas furnace and that s the exhaust vent.

A high efficiency furnace uses a different type of venting system because it extracts the heat that remains in those combustion gases before venting the resultant mixture of water and carbon dioxide. That depends on whether you have a standard efficiency or a high efficiency furnace. It is easier to go through the wall next to the furnace and makes it a lot easier to deal with. Match the vent pipe to the furnace maker s recommendations either sheet metal or vinyl.

In newly built homes these vents will usually exit thru the roof. As the gases are cooler pvc cpvc or abs piping can be used to carry the exhaust to the outside. If you are venting a high efficient furnace with the pvc piping you can go through a roof or wall. That s because the combustion byproducts are in a gaseous form so the gases can float up through the flue pipe and out of your roof.

If your furnace has an afue rating of 90 percent or above it will have a flue pipe that goes out of the side of your house. The two systems use different venting systems. Since it takes less energy to move the cooled exhaust horizontally he furnaces typically exhaust to the side of a building rather than the top. Depending on the installation a high efficiency furnace will have at least one and sometimes two pvc pipes exiting the home.