Why Furnace Blowback Occurs And What A Heating Contractor Can Do About The Problem

7 February 2022
 Categories: Construction & Contractors, Blog


One of the reasons it is so important to hire a heating contractor to check out your gas furnace every year is so you can prevent a problem known as blowback. Blowback is a potentially serious problem, but it can usually be prevented with professional maintenance. Here's why blowback occurs, signs your furnace has a blowback problem, and what a heating contractor can do about the problem.

Blowback Happens When Gas Is Slow To Ignite

Blowback is caused when gas builds up in the furnace and then ignites all at once. Your furnace is supposed to ignite as soon as gas is supplied, but if there is a malfunction with the furnace, gas doesn't ignite right away. Instead, gas collects for a while and then suddenly ignites. As you can imagine, this is hard on your furnace and potentially dangerous to your home and family.

Signs Your Furnace Could Have A Blowback Problem

When the collected gas ignites at once, you'll usually hear a loud bang. The larger the amount of gas that collects, the worse the problem is, and the louder the bang. In addition, soot can puff out of the furnace when the gas ignites. If you notice soot outside of your furnace, you may want to call a heating contractor to find out if your furnace has an ignition problem.

Repairs A Heating Contractor Might Make

Blowback is a problem that you shouldn't ignore. The small explosions could cause the heat exchanger to crack, and that's an expensive part to replace. Plus, if there is a lot of soot buildup, a lot of soot could get blown into your house and affect air quality and make a mess that's difficult to clean up.

The repairs needed for this problem often include cleaning parts in the combustion area. However, the acid byproducts created by a gas furnace are often enough to damage parts of the metal furnace, so the heating contractor may need to make repairs, too. They may start by cleaning the ignition area, burners, and heat exchanger. They'll look for damage as they clean and determine if any parts need to be replaced.

The heating contractor may also inspect and clean the flue vent since it is susceptible to damage from acids. Plus, toxic gases flow up the flue to escape your house, and if they can't escape, they may build up in your furnace and contribute to blowback and acidic damage.

If you have your furnace cleaned once a year by a professional, you might be able to prevent problems with blowback. However, if you suspect the combustion area of your furnace isn't working right, call a heating contractor right away to take care of the risk of carbon monoxide escaping the furnace if the heat exchanger is cracked.