Flame Sensor Troubleshooting & Install

You can learn more about Universal Premium Flame Sensor at https://hvacrschool.com/flamesensor.

First, make sure there is no power going to the unit. To remove the old sensor, loosen the screw holding it in place. Once you remove the screw, the sensor should come right out. Check to see if it’s dirty or otherwise would benefit from being changed out. You can also use your meter from end to end to do a continuity test and check for cracks.

When replacing a rod, the new one should have the same angle so that it can make contact with the flame. If you are using a universal sensor, check the manufacturer-provided charts to make sure you bend and cut the new sensor correctly.

The White-Rodgers Universal Premium Flame Sensor comes with a bending sleeve so that you can bend the sensor without dirtying it with the oils of your fingers. Be sure to know how far you need to bend the rod and use the manufacturer’s instructions as a reference. Place the rod against the edge of a surface with the flange pointing up and bend it according to the chart. After you bend the rod, you can cut it if necessary.

After you mount the new sensor, you can test a flame rod using the microamp scale on your meter. This test will tell you if the rod is sending a DC signal to the board; you will generally pick up between 1 and 10 microamps.