A flame sensor is a very small and specific component of a furnace, but when it is malfunctioning, it can completely shut down the operation of your Newtown home’s furnace. To start with, let’s summarize how a flame sensor works.
The flame sensor is a rod that sits directly in the path of one of the burners in your furnace. When the burner is on, the flame passes by the tip of the flame sensor, heating it up. If the furnace is on but the flame sensor is not hot, the furnace automatically switches off to avoid a continuous gas leak. So, the flame sensor is a safety measure.
Sometimes, though, the furnace can be operating just fine, and the burners are firing perfectly, the flame sensor still sends the signal that there is no flame and shuts down the furnace. This is obviously a problem.
Often, this is just a symptom of build-up on the flame sensor that is insulating it and preventing it from heating properly. We strongly recommend that you call a professional to repair it; here are the steps that they will follow:
- Locate the flame sensor on the furnace. It is a thin metal rod that extends through a bracket and into the path of the flame as it is expelled from one of the burners.
- Turn off the power to the furnace.
- Loosen the bracket holding the flame sensor in place and gently withdraw it.
- Using fine grit sandpaper or emery cloth, gently rub away any combustion build-up that has accumulated on the end of the flame sensor.
- Making sure all the build-up has been removed, replace the flame sensor in the bracket. Turn the furnace back on to test it.
If all went well, the furnace should remain on now, until the desired heating temperature is reached. Most often, the problem is as simple as giving the flame sensor a good cleaning up. Since you are dealing with quite delicate equipment, you can understand why it is so important to call in a professional if suspect a problem with your flame sensor.