How To Bleed an Oil Furnace

Don't fret, if you've tried the furnace reset button, check to make sure there is fuel oil and your furnace still wont start.Check the fuel source and make sure the line to the furnace is free of air before calling the repairman or shopping for a new furnace.Running low on fuel can cause a furnace to not restart even after you replenish it.If you bleed the oil furnace line, you can start it up again.

Step 1: Before starting work on the fuel pump, turn off the furnace.

Depending on your model, you may need to flip a switch near your furnace or turn it off at the breaker.You can turn off the gas using the shut-off valve.

Step 2: There is a bleed screw on the fuel pump.

A small nipple-like screw is what it is.

Step 3: Under the screw, place a small bucket or pan.

The bucket will catch fuel when you bleed an oil furnace.If you can't put a bucket or small tray under the bleed screw, use a flexible tubing that is big enough to fit over it.If you want to fit the tray or bucket, place the tube over the bleed screw.

Step 4: To loosen the bleed screw, use a small crescent wrench or pliers.

When you bleed the oil furnace, make sure the screw on the pump is loose so it doesn't fall off.

Step 5: To turn the furnace on again, push the reset button.

Air and fuel will leave the bleed screw as the furnace starts to suck fuel in.Put your pliers or wrench on the screw to tighten it.If you loosened the screw too much, it will remain in place.If the furnace cycle ends before the air and fuel mixture stops sputtering, you need to push the reset button again to continue the bleed process.Some furnaces won't allow you to reset more than one or two times.The reset button can be held until the furnace kicks in again.

Step 6: As soon as the air stops sputtering out, tighten the screw.

Don't tighten it too much.Replacing a stripped bleed screw can cost a lot.

Step 7: Let the furnace run.

It shouldn't have any problems now.Check the line for air again if it doesn't restart again.You may not have gotten all the air out the first time, or you may have a problem with your fuel line.