After a snowstorm, it’s important to check that snow is not blocking the furnace intake and exhaust
If you use a high efficiency gas furnace, you’ll have two pipes outside of your home. The intake pipe pulls in fresh air for combustion, while the exhaust pipe expels the by-product of the heating process. To work safely and efficiently, these pipes need to be clear of any obstruction—including snow.
Tip: You should identify where these pipes are before a major snowfall, that way you’ll know where to look when the snow has accumulated.
If your furnace is having problems starting, or it is trying to start but won’t, you may have blocked airflow from the intake and exhaust pipes.
One of the most common causes for blocked air intake is snow and ice, particularly significant snow that is blowing and drifting. With all the snow we have had this winter, even if you aren't having trouble with your furnace, it's a good idea to check your intake and exhaust pipes.
At Bravura, we recommend that you check your intake and exhaust pipes regularly to be sure they are free from blockages. If blocked, not only is the efficiency of your furnace compromised but carbon monoxide can quickly fill a house creating a life-threatening hazard.
How To Check Your Exhaust Pipes
1. Look at your furnace and find the plastic (pvc) intake and exhaust pipes. You can then follow them to see where they exit the building. It will most likely be through a wall near the furnace.
2. Go outside and look for the intake and exhaust pipes, based on where you located that they exited the building. Often, they will be a set of curved pipes near the foundation of your home. Some older systems have the intake and exhaust pipes on or near the roof. If this is the case, you will need a ladder to examine them.
3. Examine the intake and exhaust pipes, looking for anything that could be blocking the pipe. For example, leaves, dirt, snow, or ice could clog a pipe. If you have shrubs that are planted too close to the pipes could block airflow. Ideally, the pipes should be 1-foot above the anticipated snow level and 3-foot area around the pipes should be completely clear. Don’t forget to check inside the pipe, as well, to see if anything has blown inside.
4. If you find any obstructions, carefully remove it. If you have been having trouble with getting your furnace to start, you should be able to start your furnace now that the obstruction is gone. If not, look for starting instructions. These are often put in a plastic bag on or near the furnace or inside of the access panel. If it does not work after following start-up instructions, there is may still be an obstruction or some other cause and we recommend you call a professional to have a look.