soulman wrote:does the pilot look strong? could be something in the injector or fluff in the oxy pilot. There's a hole in the pilot assembly just down from the pilot flame, put the hoover around there. If there's fluff in there it will make the pilot pull away from the thermocouple. Maybe on full power there's enough residual heat to hold the thermocouple. If in doubt though get it service by a RGI.