What a Flame Sensor Is and Why It Matters

Setting up your routine furnace maintenance helps keep your heating equipment operating up to 30 percent more efficient and helps extend the life of your furnace. But things could still stop working, 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 have to have your flame sensor replaced.

Also, what is a flame sensor?

A flame sensor is a critical safety component on your gas furnace. During the ignition cycle, your gas furnace undergoes a process where a spark or a hot surface ignitor will actually ignite the gas. When the gas is ignited, the flame sensor generates a current of electricity. This is calculated in micro amps. If the furnace’s control board does not read the proper level of micro amps, the furnace will stop giving the system fuel to stop 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 determine if a soiled flame sensor is causing 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 reason, the furnace expert will clean the sensor with steel wool. If dirt was the single factor, we will see a significantly higher amp reading. If the reading shows no change, the technician will continue with the heating equipment repair diagnostic process.

If you aren’t sure your heating equipment is going to survivie these last few weeks of winter, give Service Experts Heating & Air Conditioning a call and we’ll come out and give you a full furnace maintenance or a complimentary in-home estimate on a new HVAC system.

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