What a Flame Sensor Is and Why It Matters

Scheduling your routine furnace maintenance helps keep your heating system working up to 30 percent more efficient and helps extend the life of the equipment. 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 control valve. Now your find out the flame sensor has to be replaced.

Also, what is a flame sensor?

A flame sensor is a crucial safety component on your gas heating equipment. During the ignition sequence, your gas furnace enters 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. This is quantified in micro amps. If the furnace’s control board does not read the correct level of micro amps, the furnace will no longer give the system fuel to stop an explosion.

Over time, if the flame sensor is not adequately cleaned, oxidation or carbon buildup can hinder the flame sensor’s ability to operate properly, which can cause the furnace to malfunction.

The way to determine if an unclean flame sensor is the reason 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 culprit, the furnace expert 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 carry on with the heating system repair diagnostic process.

If you aren’t certain your heating system is going to make it through these last few weeks of winter, give Teays Valley 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 furnace.

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