Welcome! Here are some tips for using this forum.
issue with Bryant three wire pilot
I was posting to see if anyone had a had a similar issue with a carrier/ bryant furnace that was very popular in the early 90's. The furnace in question is a Bryant model# 394gaz048125. The furnace just had the three wire pilot, and the gas valve replaced. The problem is that it is not establishing pilot most of the time. When it does it has no problem with the pilot switching over, and energizing the main valve and lighting the burners. The pilot will spark, but will not light. It is like the gas is just going around the pilot burner, and not igniting. I even tried an orifice in the pilot burner that you could push a 1/16" drill bit through, and still no luck. You can actually light the furnace manually with a match, and then everything will work like it should for one thermostat cycle. But that is something that I tried just to see if everything worked, and obviously not something that I want the customer to do. I don 't know what else to do other then to change the electrode on the side of the pilot burner. The furnace is old and probably should be replaced, but that does not excuse it from not lighting now. Any suggestions would be much appreciated. thanks to all.