What a Flame Sensor Is and Why It Matters

Setting up your routine furnace maintenance helps keep your heating equipment working up to thirty percent more efficient and helps extend the life of your system. But things can still malfunction, and when they do, you may feel like there is always something else.

This time it’s your motor, next time it’s your pressure switch. Now you need to replace your flame sensor.

By the way – what is a flame sensor?

A flame sensor is a crucial safety component on your gas heating equipment. During the ignition cycle, your gas furnace goes through a process where either a spark or a hot surface igniter actually ignites the gas. As the gas is ignited, the flame sensor produces a current of electricity. This is quantified in micro amps. If the furnace’s control board fails to read the proper 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 restrict the flame sensor’s ability to function properly, which can cause the furnace to malfunction.

The way to determine if a dirty flame sensor is causing a furnace malfunction is to take a micro amp draw reading, which an expert furnace technician can provide you. If a dirty flame sensor is the reason, the technician will clean the sensor with steel wool. If dirt was the single factor, we will see a notably higher amp reading. If the reading shows no change, the technician will proceed with the heating equipment repair diagnostic process.

If you aren’t confident your furnace is going to outlast these last few weeks of winter, give A1 Chesney Service Experts a call and we’ll come out and provide you with a full furnace maintenance or a free in-home estimate on a new heating system.

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