How to Bleed & Restart Your Furnace After Running Out of Heating Oil

PICTURE THIS!  

You’re in the middle of Sullivan County, NY, Orange County, NY, Ulster County, NY and Pike County, PA during the winter and your oil furnace has run out of fuel oil.  

If the furnace doesn’t kick back on after refilling the tank, you may need to bleed and restart your furnace manually. 

You can try bleeding the furnace yourself, but be careful. If you consider yourself handy or confident that you know what you’re doing, be sure to do your homework beforehand.

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The only type of furnace you can bleed and restart is an oil furnace. If you have a gas furnace, or aren’t sure what kind of furnace you have, don’t try to bleed the furnace yourself. 

If, during the bleeding process, it becomes difficult or you’re unsure how to bleed; stop, turn off your furnace and call a professional.

Step 1: Fill the Fuel Tank 

If you let your oil tank get too low or are running out of heating oil, your furnace might shut off and stop producing heat.  Your first step is to refill the fuel tank. Bleeding the furnace won’t help you at all if your tank is empty when you start the process.

Step 2: Hit the Reset Button

Once the tank has been refilled, your next step is to hit the reset button.  The furnace should start working again on its own.  Bleeding the fuel line isn’t necessary unless the furnace doesn’t restart over you’ve added more fuel oil. 

Typically, the reason for bleeding the furnace has to do with fuel levels.  If you let the oil completely run out, that’s when the furnace may need extra help starting up again.  To prevent this, refill the tank before the oil gets extremely low.  You’ll also keep yourself from freezing when the furnace shuts off.

Step 3: Turn off the Furnace

If hitting the reset button doesn’t work, you have to bleed the furnace to get it working again.  Start by turning off the furnace.  A switch should be located directly on your furnace for this.  On many furnaces, the reset button automatically shuts off the unit, so you may not need to switch off manually.  You will see a red light if your reset button has the unit turned off already.

Tools you will need:

Step 4: Collect Your Tools 

• Adjustable wrench or Allen key
• Flexible nylon tubing with a 1/4 inch diameter (1 foot should be adequate)
• Container to catch oil waste (old bucket or coffee can will work)
• Cat litter or saw-dust in the container’s bottom to avoid splashing
• OR an empty bottle, preferably 32 ounces, if you want to reuse the oil
• Old towel for your hands

You will need an adjustable wrench to fit the bleeder valve or an Allen key.  If you’re not sure which will fit your furnace, check your manual or bring both along and see what’s appropriate.  You will also need approximately one foot of flexible nylon tubing with a 1/4-inch diameter.

Next, you will need a container to catch the oil waste that will drain out of your furnace.  Use an old bucket or coffee can.  If you don’t want oil to splash put kitty litter or sawdust in the container’s bottom.  Or, if you wish to reuse the the fuel you bleed into the container, use an empty bottle.  Make sure the container is clean and do not fill it with anything.  You can return the fuel to the unit when you’re finished with the bleeding process, but only if the oil comes out clean!!  If you see sludge, do not reuse it!

Finally, don’t forget to bring an old towel with you for your hands.  There is a chance you may end up with some oil on your so wear clothes you don’t mind getting dirty.

Step 5: Find the Bleeder Valve

To find the bleeder valve, you’ll need to find the fuel pump.  The fuel pump will have tubes going to it.  The bleeder valve is going to be on one side of the fuel pump, and it’ll have a hex nut on it.  The hex nut can be metal or a rubber plug.  If you don’t see it right away, don’t panic!  It’s a little hidden on some furnaces.

Loosen the nut to ensure you can turn it at the proper moment.  Then tighten it up again, about a quarter turn, so oil doesn’t dribble out.  Don’t unscrew the nut completely.

Step 6: Attach Nylon Tubing

Slide the tubing into the bleeder valve and position it so its other end rests in the container.  You can choose to use the tubing into the bleeder valve or simply let the fuel dribble straight out into the container.  If you don’t use tubing, please be aware that the oil may splash, and the process will be messier than using the tube.  To avoid additional spillage on the floor, ensure the container is sitting directly beneath the valve. 

If you have a second person helping you, that person can hold the container directly beneath the valve to catch the oil.

Step 7: Turn on the Furnace and Unscrew the Valve

Next, turn on the furnace.  Remember how you loosened the valve before, then tightened it just enough to be sure you could turn it again quickly?  Now’s the time to loosen it.  You’ll probably need less than one turn to get the oil flowing.  Loosen the valve until oil and air start to come out.  Let it drain until solid fuel comes out.

If nothing comes out of the valve, you may have to hit the reset button after you’ve flipped the on/off switch.  If your furnace automatically shuts itself off with the reset button, you may have to give it a couple of tries.  If the unit doesn’t turn on, call a professional to take a look.  The problem might be a clog, damaged fuel line or pump issue.

Step 8: Tighten the Valve

When the oil comes out in a steady stream, tighten the valve.  At this point, the burner should turn on.  You’ll know it when you hear it; this is the sound you associate with the furnace kicking on.  If that happens, congratulations!!  You’ve successfully bled and restarted your furnace.  Remove your tubing, clean up your container and enjoy the warmth!

If the unit’s burner doesn’t turn on after bleeding the oil the first time, try again.  Start by loosening the bleeder valve and letting fuel come out.  You can try this several times.

However, if your furnace isn’t firing until you’ve done it numerous times, you may have worn out parts and need to call someone to look at it.  It should take more than once or twice to bleed and restart your unit when its in proper working order.

When All Else Fails… Call a Professional

A professional can accurately diagnose why your unit isn’t starting.  If at any point in the process of bleeding the furnace something doesn’t seem correct or you lose confidence, it’s time to call a professional.

Similarly, if the process doesn’t work, something else is wrong and you need a technician to examine the furnace. Even if bleeding the furnace does work, but you find you have to do it frequently, it’s probably time for a professional opinion.

If you live in the areas of Sullivan County, NY; Orange County, NY; Ulster County, NY; Pike County, PA Combined Energy Service can repair your oil furnace and dispatch an emergency technician at any time.

If you’re unable to bleed your furnace, call us at 800-874-1975. We’re here to get your home warm and your family comfortable again.