Gas and Oil Home Heating Furnaces - Only two burners light

I have a Rheem gas furnace, probably 1994 issue. It has a manual pilot light and four burners. Most of the time only two burners light, every once in a while three and very seldom all four. During extreme weather my furnace runs a lot and the back bedrooms don't get much heat. The two burners that work are the middle burners next to the pilot light and the outside burners are the ones that don't light. I tried looking at the orifice where the gas comes out with a mirror and it looked good. Any thoughts on what I can do?

Remove the burners and blow them out real good with canned air. Make sure you get the transfers good since spiders like to live in them.

I sure hope you are NOT running it like this all the times????? :eek:

WIth raw gas going in to the heat exchanger is waiting for expostion to happen!

Remove the buerners and make sure the are clean, and also the carryover/cross over burners are clean too..

If no luck, make sure the orfice are clean, other wise get a pro in before something deadly happens.

Just make sure when you pull the burners out that you clean the pilot strip in the front. Thats what takes the gas over to the pilot light to make them light. Re set the air on them with a soft blue flame not a hard flame.

ED ;)