I have a Rheem RGRM 90k furnace and was counting the flasning red led to see what my AC airflow was and noticed that the STATUS led was steady on. Manual states that this is "Normal fault detected". Anyone know what this means?
I don't know for certain, but it appears to be the normal indication. Mine has always been on as best I can recall (it is now) and seems to be working fine. (Perhaps it shuts off during actual furnace firing...I don't recall.) Since it is a Green LED having it constantly lit would usually indicate a "system go" condition.
The "troubleshooting chart" for the furnace really only mentions this light if some other problem is occurring. It the system is operating normally you don't even get to this point. And in the top entry if you have a problem elsewhere (with the induced draft fan, IDM, not starting on high speed) then on/off/blinks for the "status LED" all lead to other points as follows.
1. Off...says check the IFC, the control board. <==indicates some sort of fault of the control board is the way I interpret it. So "off" in this situation appears to be "bad board/board trouble."
2. Blinks...have various sources to check.
3. On...says check out the IDM and connections to it. <==suggesting the board is doing what it should telling the IDM to run, but that the IDM is not responding as it should.
The other instance on the chart where the status LED is mentioned is when the IDM doesn't shut off. It only seems to care if there is a status LED blink code in this situation, on/off are not addressed.