Skip navigation

Serving the entire Twin Cities

24HourEmergency Service

763.772.0815

Two Generations of Quality Through Integrity

Can You Use an Existing Chimney with a New Furnace?

question-mark-blueAll heating systems that use oil, solid fuel, or natural gas to run need some sort of ventilation. Your gas furnace uses combustion to produce heat, but the process also leads to the development of some pretty unpleasant byproducts, including carbon monoxide—a dangerous, toxic gas.

Sometimes, we see multiple appliances using the same flue vent system for multiple appliances, but this isn’t always a possibility. In fact, we almost always recommend against it if you have an older chimney and a new high-efficiency furnace. Can your new furnace be vented through the chimney?

How New Furnaces Vent

Typically, new furnaces vent through a flue pipe that goes from the furnace unit straight out the side of the home. The furnace pipe is horizontal and relatively short, and it’s this way for a reason.

New furnaces are built to be highly efficient, which means they don’t give off a lot of heat during ventilation—most of it stays in the air. Because there are fewer byproducts to vent, your chimney may be too wide, which could result in improper ventilation. This allows water vapor to build up in the chimney which can do permanent damage.

The Condition of Your Chimney

There’s also the concern that your chimney may not be in the best condition to vent byproducts from your furnace, let alone that it’s not the right size. Many chimneys constructed into homes in our area are quite old, which means they do not have the proper lining to vent a furnace (or even to safely use with a fireplace).

All in all, building codes may prevent technicians from using your chimney to vent a furnace anyway. The standard piping used to ventilate new furnaces should do just fine. In the meantime, fix those pesky chimney problems with the help of our expert chimney sweeps!

Contact 2nd Generation Chimneys, Inc. We offer fireplace and chimney repairs in Minneapolis, MN.

Comments are closed.