I noticed two days ago that my furnace was running but the house seemed to be getting cold. I checked the thermostat and sure enough it was 60 degrees, when it was set to be at 71. I turned the furnace off, turned the gas off, and then relit it and it turned back on. Worked fine for awhile and then the same problem occurred again. This time I watched the furnace turn on. The gas was lit but only for like 10 seconds then it went out. The furnace tried to relight again but the same thing happened. Now the furnace is just running with no flame. And the air coming from the vents is not very warm. Does anyone know what may be the problem? I am REALLY hoping it is something I can fix myself!! Thanks for any help!

Either a pressure switch problem, or the flame sensor. A dirty flame rod will only let the flame stay on for 5 seconds or so. It is a small rode located on the opsite side of the ignitor. Sticking down in the burns just rub it with some sand paper or steelwool.

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