The vast majority of flame sensors we sell replace good sensors in spite of us recommending against it. The low voltage that is transiting the flame sensor through the flame is easily blocked by the invisible residue that builds up on the sensor. It would be easier to believe if the coating we sand off was visible in some way. Sensors go bad when the ceramic insulator cracks, otherwise they can be sanded endlessly.
The ignitor, the gas valve, and gas pressure can be a factor in those symptoms.Ĭall the U-FIX-IT Appliance Parts store nearest you for free personalized diagnosis assistance.
If the flame does not burn steadily on the flame sensor it can interrupt the circuit. If the flame is slow to light the “time out” can occur even though there is a good circuit back to the control board. The control board will “time out” if it does not detect the flame (low voltage) within the time period. The control board sends out a very low voltage to the flame sensor that conducts through the flame to ground and back to the control board. The flame should impinge on the flame sensor.
The burner should produce a steady blue flame. You did not mention if you are experiencing these symptoms after replacing the flame sensor Cleaning or replacing the flame sensor is the usual solution.
Purchase Furnace Partsħ blinks is the error code for “flame could not be established.” The classic symptom for flame sensor is: the burner flame comes on but goes out within seconds. Note – If this repair does not restore normal operation call for free diagnosis assistance or bring the flame sensor in to the U-FIX-IT Appliance Parts store for free testing and inspection.
Broken or cracked ceramic are signs that the flame sensor is defective. Because of this coating, electricity flow is restricted and the furnace control system “thinks” the burner has failed to light and shuts off the gas as a safety measure even though everything has worked as designed. What is happening? – Over time, a coating can form on the metal rod of the flame sensor that is difficult to see. They are powered by a single wire carrying a small amount of electricity (less than 10 DC microamps). Flame sensors vary in size (2 to 4 inches) and shape (see examples below). Not all furnaces have a flame sensor, but if your furnace has one, it will be mounted close to the burner with the metal rod positioned in the flame. What is it? – This symptom is often caused by a dirty flame sensor that can be easily cleaned. Symptom – Burner lights off, but goes out quickly.