I have a Coleman Furnace Model 7975-856. The Pilot randomly goes out. Sometimes the furnace cycles once and it goes out. Other times it may cycles several times before going out. I replace the thermocouple and cleaned the pilot, but still have the same issue. In effort to test the pilot itself, I turned the thermostat completely down and lit the pilot. It stayed lit that way for several hours with no issues. Once I turned the thermostat back up it went out after one or two cycles. Could it be the gas valve that is bad? And if so, any clue where to find a cheap one?