I recently replaced the stack relay on my hot air furnace. I tested the oil gun by plugging into 110 volts,it ran. I tested the transformer,got about a 1 inch arc. The blower motor also works. The old relay failed so I changed it out,it worked fine for a few days,then the furnace kept running after the temp set on the thermostat was reached. The lower contact bar on the top contacts stuck (welded) closed. I believe this was the problem that caused the failure of the old relay,because the same bar was blue,like it had overheated. What would this indicate as a problem? What does the top set of contacts control? I killed the power to the furnace and pulled the contact open with a small screwdriver. I think it is OK because it came apart fairly easily,but I don't want to burn out the new relay using it. I need to fix what is causing the problem.

Members, The heater works great with the burner compartment door off. My question is why does it not work with the burner door on. With the door on when the thermostat calls for heat the heater starts the ignition process. Soon as the burners light about 2 seconds later they go off. The heater makes a second attempt. Usually on the third or forth attempt the heater kicks on. Once I put the door on the first 2 times the thermostat calls for heat the burners kick on but on 3rd or 4th attempt. After the first 2 calls for heat with door on the heater never kicks on again so I take the door off and it works great all the time. A couple of weeks ago I had the flame sensor replaced. Tech rigged old flame sensor so we could have heat. When he put part in and verified it worked he said leave burner door off because compartment is not getting enough air If anybody knows what I can try to make heater work with burner Door on please let me know Thanks Frank