Oil furnaces are a really valuable part of your home, and they can help keep you toasty during chilly weather. The igniter, or the probed electrodes attached to the fuel nozzle, is an especially valuable part of the furnace, as it helps generate the heat that goes through the furnaces and warms your home. If your igniter isn't working properly, you'll have to deal with some unpleasant, cold temperatures. While you should always consult a heating and cooling professional with serious concerns, there are a few ways you can tinker with and test your furnace's igniter and fuel nozzle to get it back in working condition.
Part 1 of 2:Cleaning and Realigning Your Igniter
1Power down the furnace and close the oil valve. Search around your furnace for an on and off switch. Move this switch to the off position, then search for the oil line, or the pipe that feeds oil into your furnace. Twist the valve clockwise to lose the oil valve completely, which will stop oil from flowing into your furnace.
The on and off switch is likely attached to your furnace or somewhere else nearby. If you're having trouble finding it, look at your furnace's schematics for guidance.
2Turn off the circuit breaker that powers the furnace. Keep in mind that your oil furnace uses electricity to power the igniter, so it's hooked up to a circuit breaker. Switch off any power lines that connect to your furnace, or else you may give yourself a nasty shock while you try to adjust your igniter.
Double-check your home schematics to see which circuit breaker or power lines feed into the furnace.
3Unscrew the access panel from the furnace. Look for a large, metal rectangle that's screwed into place on the front of your furnace, otherwise known as the access panel. Remove each of the screws with a screwdriver, then set both the access panel and the screws aside.
The access panel covers the igniter.
4Remove the metal tip from the side of the blast cone. Look for the blast cone, which is a curved metal structure attached beneath the main burner in your furnace. Search for a cowler, or conical metal piece, that's attached to the side of the blast code. Twist or slide out the cowler so you can access the fuel nozzle and igniter.
The cowler may twist off like a screw, or you may be able to slide it out, depending on the type of furnace you have.
The igniter refers to the 2 large electrodes connected to the fuel nozzle.
Did You Know? The blast cone is the large, metal compartment that holds the fuel nozzle and igniter. The fuel nozzle is a curved, cylindrical pipe, and the igniter refers to the 2 large electrodes connected to the fuel nozzle. Once the cowler is loose, you can pull the fuel nozzle and igniter out of the blast cone pretty easily with a sharp tug, or put it back in place with a firm push.
5Clean out the fuel nozzle and put the clean parts back in place. Gently pull the fuel nozzle and igniter out of the furnace with both hands and set it on a clean, flat surface. Spritz the tip of a clean cloth with an all-purpose cleaner spray and clean off the cowler, as well as any screws or bolts attached to the nozzle. Spray the cleaning spray down the fuel nozzle along with some compressed air to clean out any built-up oil. Once the nozzle and igniter are clean and dry, put the cowler and other small parts back in their rightful places.
If you don't feel confident disassembling and cleaning the nozzle on your own, contact a professional for help.
Make sure that the cleaning spray is safe to use on metal.
6Move the igniter wires to the tip of the ignition transformer. Insert the fuel nozzle and igniter back into the blast cone area of the furnace. Look near your ignitor to find the ignition transformer, or a small metal box that helps create a spark in your furnace. Search around the ignition transformer for a place to connect the 2 wires from your igniter.
Don't worry about rewiring anything—just make sure that the wires attached to the igniter connect over to the transformer.
7Power on your circuit breaker again. Flip back the switches that power your igniter. Leave the access panel off for now so you can examine your igniter up close.
Part 2 of 2:Checking for Power
1Press the ignition button next to the furnace to see if it sparks. Search around your oil furnace for a red button or other prominent button that ignites your furnace. Press this button once, and look at your igniter to see if there's a visible spark.
If you can see a spark coming from your igniter, you can replace the access panel and turn the power and oil back on.
2Shut off the circuit breaker if you don't see a spark. Return to your circuit breaker and flip off any switches that connect to your oil furnace. If you don't turn off these switches, you could be setting yourself up for a nasty shock.
3Test the wires on the ignitor transformer with an ohmmeter to see if they work. Power on an ohmmeter or multimeter and make sure that the device is set to read ohms, which is represented by an omega symbol. Touch the metal tips of these leads to the place where the 2 wires connect to the ignition transformer and see what reading you get. If the ohmmeter reads “0,” you'll need to replace the electrodes in your igniter. If you get a reading on your device, then the issue is in some other part of your furnace.
4Check the ignition tip on your ignition transformer with an ohmmeter. Double-check that your device is still set to ohms, then place the metal tips of your ohmmeter leads on the ignition transformer itself. If your device doesn't pick up a reading, contact a heating and cooling professional to replace your transformer overall.
5Replace the access door and turn the power and oil back on. Check that your fuel nozzle and igniter are securely attached inside the blasting cone with a cowler, then screw your access door back into place. Take a moment to switch your circuit breaker back on, then turn your oil valve counterclockwise so it releases oil again. Once the electricity and oil are powered on, switch your furnace back on.