Furnace Tips: Recognizing Flame Colors

Needless to say, your furnace is a very important piece of equipment, so it pays to have even a basic understanding of how it works. Keeping track of how efficiently it’s operating and knowing when to have it serviced can save you hundreds–if not thousands–of dollars in the long term. Home heating companies also highly recommend familiarizing yourself with the different flame colors your furnace may produce and learning the meaning behind each.

Furnace Tips

What Color Should Your Furnace Flame Be?

Your natural gas furnace should produce a very distinct blue flame with a lighter blue triangle at its center. There may also be a tiny bit of yellow around the tip. A roaring blue flame indicates efficient combustion, meaning the gas is being burned efficiently and very little is going to waste.

Blue flames are also hotter. If the flame your furnace produces is yellow, green or orange, or if you see little pops of these colors in the flame, then you need to seek the help of a professional. This likely means that you have a combustion problem that should be addressed by a properly- licensed HVAC company.

In addition to inefficient combustion, when the flame is a color other than blue, this could also mean higher heating bills and more soot. However, the real danger of a non-blue flame is the increased amount of carbon monoxide produced by the combustion process. Carbon monoxide has been dubbed the “silent killer”, as it’s an odorless, colorless, and tasteless gas that can cause headaches, nausea, hallucinations, blackouts and even death.

Stone Heating and Air is one of the leading furnace and air conditioning companies dedicated to providing quality HVAC services to residents in Oregon. For all your heating and cooling needs, be sure to give us a call at (541) 855-5521 or fill out our contact form to schedule a free appointment.

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