The Comfort of Home

As a homeowner, maintaining your home's oil-burning furnace is an essential investment and task this winter. While your furnace may have run fine for the last few years, there will inevitably come a time when you need a heating contractor to do some repairs, even if you keep up on maintenance. For example, if your furnace starts to sputter and flicker, here's what you need to know.

How Do You Know If Your Furnace Is Flickering?

You might wonder how to tell if your furnace is flickering without actually sitting in front of it and watching the burner flame. In fact, if the flickering is intermittent, you may not notice it without sitting in front of it for several cycles. However, there is another way that you can tell if the furnace is flickering.

When you listen to your furnace running, it should have a consistent, steady sound. If you start to hear noises as though it's cutting out, or you hear sounds like air is passing through the furnace itself, that's an indication that the flame is cutting out and flickering when the furnace runs.

What Causes The Furnace To Flicker?

Ideally, your furnace burner flame should burn steady and consistent when the furnace is running. This flame is fueled by the oil that's supplied from the fuel line as well as the air that's pushed through the system. The majority of instances of furnace flickering are caused by an interruption in the fuel supply. When the oil doesn't flow consistently, the burner will flicker every time that oil supply is interrupted. It's like any other fire. An interruption in fuel will disrupt the flame.

How Does The Fuel Supply Get Interrupted?

The most obvious cause of interruptions in the fuel supply to your furnace is a low oil level in the tank. If you're due for an oil delivery, the supply could be running low. This may cause the fuel pickup line in the tank to draw oil intermittently. Make sure you have sufficient fuel in the tank before you start troubleshooting any further.

If there's sufficient oil in the tank, the problem is somewhere in the delivery to your furnace. It could be that there's a clog in the fuel nozzle, or your fuel filter may be dirty and in need of replacement. However, if you've had the system maintained recently, this is unlikely to be the problem.

Another common cause of flickering is when there are air pockets in the fuel supply line. This can occur for many reasons, but typically it's because a fitting on the supply lines is loose and letting air in the system. It could also be due to a crack in a line. It's important that you have this inspected right away by a heating contractor because a crack in a fuel line could lead to oil leaking out, which is costly and bad for the environment.