What a Flame Sensor Is and Why It Matters

Setting up your annual furnace maintenance helps keep your heating system operating up to 30 percent more efficient and helps extend the life of your furnace. But things may still go wrong, and when they do, you may feel like it’s always something else.

This time it’s your heat exchanger, next time it’s your control board. Now your find out the flame sensor has to be replaced.

Also, what is a flame sensor?

A flame sensor is an important safety component on your gas heating equipment. During the ignition pattern, your gas furnace goes through a process where either a hot surface ignitor or a spark will actually ignite the gas. When the gas is ignited, the flame sensor creates a current of electricity. The current is quantified in micro amps. If the furnace’s control board fails to read the correct level of micro amps, the furnace will quit giving the system fuel to avoid an explosion.

Over time, if the flame sensor is not cleaned properly, oxidation or carbon buildup can impede the flame sensor’s ability to work properly, which can end up causing the heating system to malfunction.

The way to establish if an unclean flame sensor is to blame for a furnace malfunction is to take a micro amp draw reading, which an expert furnace technician can give you. If a dirty flame sensor is the offender, the furnace expert will clean the sensor with steel wool. If dirt was the single factor, we will see a much higher amp reading. If the reading does not change, the technician will continue with the heating equipment repair diagnostic process.

If you aren’t confident your heating equipment is going to survivie these last few weeks of winter, give Bob Brown Service Experts a call and we’ll come out and provide you with a full furnace maintenance or a no-charge in-home estimate on a new heating system.

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