My corona fh-321 kerosene heater starts and runs for about 5 to 15 minutes and shuts down. Sometimes it will restart right away but sometimes I will have to wait about a minute before it will restart. But then it will shut down again after it runs a few minutes. I can read wire diagrams, schematics and do some troubleshooting. But I don't have any manuals for this heater. It was operating fine. Can you please help me with this problem and I would very much appreciate getting the manuals, wiring diagrams and wire schematics for the Corona FH-321 kerosene heater. PLEASE HELP if possible.