Problem with Clare gas furnace!!

______________________________________________________________________ This summer we moved into a home with a Clare Megasave HEMB Series B gas furnace(installed 1990) Prior to the heating season it was cleaned and serviced and it ran well for a week. Then, one night it shut down.I turned the unit power off for 60 secs.,turned it back on and the furnace fired up again. It will run fine for approx. 24 hrs. and then locks out again. I repeat the process and it runs well, but again for 24 hrs. On reading the operation manual,it mentions checking the thermal spillage switch reset button;however I can’t locate this button as shown on the furnace schematic. Could my problem be not resetting the switch or something entirely different. Can you describe this reset button or its location. Thanks for any information!! A.P. Replies: