What a Flame Sensor Is and Why It Matters

Setting up your seasonal furnace maintenance helps keep your furnace running up to thirty percent more efficient and helps extend the life of your furnace. But things can still go wrong, and when they do, you could feel like you’re always hearing about something else.

This time it’s your heat exchanger, next time it’s your control board. Now you have to have your flame sensor replaced.

Also, what is a flame sensor?

A flame sensor is an important safety element on your gas heating equipment. During the ignition cycle, your gas furnace enters a process where either a spark or a hot surface igniter will ignite the gas. Once the gas is ignited, the flame sensor generates a current of electricity. The current is measured in micro amps. If the furnace’s control board does not 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 appropriately, 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 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 offender, the technician will clean the sensor with steel wool. If dirt was the only factor, we will see a significantly higher amp reading. If the reading does not change, the technician will continue with the furnace repair diagnostic process.

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

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