What a Flame Sensor Is and Why It Matters

Setting up your routine furnace maintenance helps keep your furnace operating up to thirty percent more efficient and helps extend the life of your furnace. But things may 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 board. Now you need to replace your flame sensor. 

Also, what is a flame sensor? 

A flame sensor is an important safety feature 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. 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 doesn’t 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 adequately cleaned, oxidation or carbon buildup can restrict 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 to blame for a furnace malfunction is to take a micro amp draw reading, which an expert heating technician can provide you. If a dirty flame sensor is the reason, the heating 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 shows no change, the technician will proceed with the furnace repair diagnostic process. 

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