I have a Rheem Criterion II (Model RGPH 07NAMGR) with the main furnace blower that runs continuously. The IFC board (62-24084-82) is giving me the three blink error (middle green light between a green and orange bulb) which I believe indicates an open limit switch. I have check the three limits (manual resets) in the burner compartment. Each of the reset switch is depressed. I did check each of the limit switch with a meter and there is no resistance indicated from the two connectors on the limit.

Is it possible that it is the flame sensor? Is the flame sensor the single rod with a single red lead near the burner?

I've check the filter and seems to be okay. Is there any thing else I should check?

Thanks

There is also a main limit on the back wall and often another in the blower compartment. Limits trip due to poor airflow. Read the FAQ at very top of heating page for more info and pictures of limits and airflow problems.

I have a Rheem Criterion ll (Model RGHP-07NAMGR) the main furnace blowers is always on. The IFC board the top green light is on, middle green light blinks and the orange bottom light isn't on. Where are the 3 limit switches so I can manually reset them to see if this solves the problem. Thank You