What a Flame Sensor Is and Why It Matters

Receiving your seasonal furnace maintenance helps keep your heating equipment operating up to thirty percent more efficient and helps extend the life of the equipment. 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 blower, next time it’s your control board. Now your find out the flame sensor has to be replaced.

Also, what is a flame sensor?

A flame sensor is an important safety component on your gas heating equipment. During the ignition cycle, 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 creates a current of electricity. The electricity is quantified in micro amps. If the furnace’s control board fails to read the proper level of micro amps, the furnace will quit giving the system fuel to prevent an explosion.

Over time, if the flame sensor is not adequately cleaned, oxidation or carbon buildup can interfere with the flame sensor’s ability to work properly, which can end up causing the heating system to malfunction.

The way to diagnose if a soiled flame sensor is the reason for a furnace malfunction is to take a micro amp draw reading, which a professional furnace technician can provide you. If a dirty flame sensor is the offender, the furnace expert will clean the sensor with steel wool. If dirt was the sole factor, we will see a much higher amp reading. If the reading does not change, the technician will carry on with the furnace repair diagnostic process.

If you aren’t confident your heating system is going to outlast these last few weeks of winter, give Calverley Service Experts a call and we’ll come out and provide you with a full furnace maintenance or a no-charge in-home estimate on a new HVAC system.

Contact Us