What a Flame Sensor Is and Why It Matters

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

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

By the way – what is a flame sensor?

A flame sensor is a critical safety feature on your gas furnace. During the ignition pattern, your gas furnace undergoes a process where either a spark or a hot surface igniter will ignite the gas. When the gas is ignited, the flame sensor produces a current of electricity. This is quantified in micro amps. If the furnace’s control board does not read the right 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 appropriately, oxidation or carbon buildup can impede the flame sensor’s ability to work properly, which can cause the furnace 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 heating technician can give you. If a dirty flame sensor is the culprit, 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 doesn’t change, the technician will proceed with the heating system repair diagnostic process.

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

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