Problem with old Rheem furnace ignition

Troublefix · 01-31-2011, 11:48 PM

I have an old 20+ years automatic ignition Rheem Furnace Mod RGNC-14KC.
After a lot of thought and research these is where I am.
1) I turned the gas off and I can see the sparks from the ignition --> therefore thermostat OK, igniter OK, DSI seems OK.

2) I was able to light the pilot with a long match after making sure all gas had dissipated. I just turned the switch on with the match in and the pilot started. Pilot stayed on, furnace kicked in, home getting warm --> flame sensor OK, Thermocouple OK, pilot orifice OK (main reason I did this was to check if gas was flowing or pilot might be blocked).

3) when I let the furnace start on its own without the match it will not. I can hear a clicking sound as if the ignition is sparking but pilot does not come on. I looked inside while this is going on and best I can tell there is no real spark just a soft spark sound. In fact when the pilot came on with the match it seem to be blowing gas quite hard. Is it possible there is too much gas blowing on the DSI preventing it from sparking or is it that there is something wrong with the ignition system?

I would appreciate any help.

**beenthere** · 02-01-2011, 04:56 AM

May not be actually sparking. Need to see if its really sparking. Might have tom pull pilot assembly and test it outside the furnace.

Troublefix · 02-01-2011, 07:57 AM

Thanks beenthere, When the gas is off I can clearly see the spark which is similar to the electronic match igniters. Can it be that the ignition is not strong enough?

Finally, since I ignited it with the match last night it has come on by itself a number of times. However it takes quite a long time to get the pilot to light.

**beenthere** · 02-01-2011, 04:31 PM

Probably needs cleaned.

Troublefix · 02-01-2011, 07:10 PM

I did try cleaning it a number of times and did not work (or maybe only temporarily). I used sand paper (the gray one for metal) with gentle pressure. Can it be damaged if cleaned with too much pressure?

I was thinking of just replacing this part but have trouble defining the correct part number. I just know that it fits the 5059-22 igniter. If I do replace it, how do I disconnect the plug from the igniter? do I just pull hard?

Thanks again for your advice.

**beenthere** · 02-01-2011, 10:08 PM

You cleaned the pilot? or did you just clean of the ignitor.

Troublefix · 02-02-2011, 01:37 PM

I cleaned the igniter. As I mentioned the pilot start if I use a match. But the igniter does not spark when the gas is on, with the gas off I can see a nice spark. (although I do not know how strong a spark needs to be.)

**beenthere** · 02-02-2011, 04:52 PM

Its possible the module is getting weak.