Posted by: Bruce on November 24, 2004 at 14:13:06

The furnace is only 4 or 5 years old. The Furnace will cycle and began to heat but after a few seconds the gas valve will shut off and the unit will began to cycle again but sometimes the unit will work correctly. I have cleaned the flame sensor and checked and cleaned the wiring connectors and replaced the thermostat. I have had a repair man look at it also, he gets it to work for a short time and then the unit begans to work only when it wants to. I sure could use some help on this?

Answer:
36c-67 is a white-rogers standing pilot 24V gas valve. Bruce has an electronic ignition type of furnace. For Dale,what happened to the gas valve's knob? As I understand that you are looking for a replacement gas knob. If the gas knob was melted, you have a serious flame roll over that is either caused by cracked heat-exchanger, blocked flue pipe or dirty burner tubes. In this case, consult a reputable gas technician.

If the problem is none of the above, check your pilot flame. Is your pilot flame strong and wrap around, (targets on ), the thermocouple? If "No" then you have a dirty pilot orifice. A weak or dirty pilot flame will be easily extinguished by the turbulence inside the combustion chamber. It is better to let the qualified technician to check it out as suggested by "HeatPro".