If you’ve recently upgraded to a new, high-efficiency furnace in your home and it has stopped working, the most common cause is a problem with the venting.

Do this first: check the vents on the outside of your home and make sure they’re not clogged with ice or debris.

If the vents are clear, there could be a problem with how the furnace vents were installed.

High-efficiency furnace vent problems

High-efficiency furnaces must be vented differently than old furnaces. This leads to many improperly installed intake and exhaust vents by installers who are unfamiliar with the newer furnaces.

And if your furnace isn’t vented properly, safety mechanisms can cause it to shut itself down.

Here are some of the most common vent installation problems:

Incorrectly sized exhaust pipe

The manufacturer will specify the maximum length an exhaust vent can be, depending on its diameter. Too long of a vent can obstruct airflow. Similarly, too many bends (called elbows) in the vent can also slow airflow.

Vents installed too close to the ground

If the exhaust or intake vents are installed to close the ground, debris and critters can easily block them.

Not enough support for exhaust pipe

If the PVC exhaust pipe is not supported well, condensate can pool in the pipe and create a block in airflow. A well-supported exhaust pipe typically has a support every 3 feet.

Exhaust pipe not properly sloped

The exhaust should also be sloped back toward the furnace. It should drop ¼ of an inch vertically for every foot it travels horizontally. Again, this will keep the moisture from collecting in the pipe and blocking airflow.

Vents exiting the home at an inside corner

The inside corners can block proper airflow to your furnace.

Get a professional’s help

These problems can be difficult to spot if you don’t know what you’re looking for. A professional heating company can give you more information on why your high-efficiency furnace has stopped working.

If you’re in the NW metro Atlanta area, we can help. Just give us a call or contact us online.

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