Furnace Keeps Shutting Off

[imported_krmereness]

My oil fired, forced air furnace keeps on shutting down. I will set the thermostat on about 76 and the furnace will run for 5-6 minutes then shut itself down before it reaches the correct temperature. Any suggestions?

[Wgoodrich]

Sounds liike you need to change your orfice. I suspect you will find soot build up inside the heat exchanger. Somewhere you will find a couple of wires coming from your control in the furnace to a device that is an electric eye that looks at the flame. If no flame is seen the furnace is shut down. If your furnace is sooted up due to a bad orfice on your burner causing incomplete ignition of fuel then the photo cell looking to see the flame will soot over thus the sensor can not see the flame causing your furnace to shut down.

Temp fix clean the electric eye looking at the flame inside the heat exchanger.

Long term fix change your orfice on your burner and reclean your electric eye looking for that flame.

Hope this helps

Wg