*Bleeding a Furnace Burner*
By: Jaden
8 April 2009

For whatever reason your furnace runs out of fuel. After having more fuel put in the barrel the furnace won't automatically start again.

The reason being is there is air in the fuel line and the reset button tripped.

Red reset button

Bleeder screw

Loosening the screw

Do not just push the red button. The burner will try to light but the button will again pop out after a few seconds. Turn the thermostat up so that it will call for heat. Get a 3/8" wrench and a container adequate enough to catch a little bit of fuel. Locate the bleeder screw. Using the wrench turn it counterclockwise about 1 complete turn and then position the container under it.

Then push the red button in and about 2 seconds later the burner motor will start. Fuel and air bubbles will exit the bleeder screw. Once the bubbles stop coming out, tighten the bleeder screw. The burner should ignite if it hasn't already.


Take the fuel you bled out and dump it back in to your tank. Reset your thermostat.

(The thermostat can be bypassed by jumping 2 terminals on the burner, but if you know how to do that, you wouldn't be reading this article.)

Note: #2 fuel oil is red in color. Most furnaces use it. This one is actually burning some diesel fuel.


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