When Your Furnace Won’t Ignite

Homeowner’s Heater Checklist: Before You Call for Repair

It can be a big problem to suddenly find yourself dealing with a broken furnace. Especially if you are discovering this in the middle of a freezing Illinois winter. We recommend that homeowners do a test run of their furnace well before winter hits. That way any problems can be detected and handled well in time before you need your heating system to work.

The first cold snap to hit the Aurora area doesn’t just mean you’re dealing with a heater problem at a time you need heat. You are also now faced with the difficulty of getting a professional heating technician to come to your home. It’s at this time when Maximum Heating and Air Conditioning and HVAC companies across the Chicago area are flooded with urgent furnace repair calls.

If you find that the cause of your broken furnace has to do with it not igniting, there are several things you can do as a homeowner that may actually fix the problem. These DIY steps may save time, money and prevent spending even one night in a very cold house.

Understanding furnace ignition sources

How to Light Your Furnace

There are 2 main ways that most furnaces ignite. Therefore, you first need to identify which of these ignition sources applies to your furnace.

Pilot Light

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A pilot light is a small flame that is constantly burning inside your furnace. Look at the bottom of your furnace for a tray where the burners are. You will see a pilot light, usually located to one side and just slightly above the burners tray. You will need to supply fire to this pilot light, either with a long match or a long lighter. Make sure the control now is set on “pilot”.

6 Steps: How to Light a Pilot Light

  1. Before even addressing the furnace itself, turn your thermostat down very low. That way the heater won’t come on immediately when you light your pilot light.
  2. Turn the control knob so that it set on “pilot”. If it was already in the on position, turn it to off and wait 5 minutes in order to clear out any gas. SAFETY WARNING: If after waiting the 5 minutes you smell gas in that area, that could mean you have a gas leak somewhere. If so, do not attempt to light your furnace yourself. Contact us to come out and ensure your lines are safe for it to be relit.
  3. Turn the knob to “pilot”.
  4. Push in the control knob. You may be able to hear the sound of gas going through the pipe. With that pressed, use either a long match or lighter to put a flame under the gas port of the pilot. If you see a small flame burning from the pilot light, continue pressing the control knob for a minute. If this is the first time lighting your heater for the season, it may take several minutes to light. The gas that is needed to ignite the pilot light has to travel the length of the gas line. The longer your gas line is, the longer it will likely take before your pilot light will ignite.
  5. Slowly release the knob. Ideally, your pilot light is still burning. Now you turn the knob to the on position.
  6. Turn your thermostat up. You should now see more flames burning in your furnace tray.

Electric Furnace Ignition

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This is the most common type of ignition source for modern furnaces. An electric ignition is considered the safer of the two as it doesn’t require gas to ignite. They are made of a metal alloy that heats up when an electric current goes through it. This heat ignites the gas/air mixture that is coming into your furnace.

You can’t relight an electric ignition as you would a pilot light. Instead, you will be checking to see if the electric ignition is lighting up in order to help diagnose the problem, which may be to replace the electric ignition.

4 Steps: How to Know if an Electric Ignition is Burnt Out

  1. Turn the power on to your furnace.
  2. Look into your furnace to see if your ignitor is glowing. They are typically located in the same place as a pilot light (see above Pilot Light section).
  3. You will hear a click when the gas valve opens, sending gas through the area with the electric ignitor. You may hear the sound of gas hissing. If there are still no flames coming up from your electric ignitor, that is a good indication that your ignitor is burnt out.
  4. If you are able to see the ignitor well, look for cracks. A crack would indicate that your ignitor is burnt out or that there is a problem with the power in supplying electricity to your furnace ignitor.

Replacing an electric ignitor may be something a homeowners can do themself – at least those who feel confident handling furnace repair that requires more than basic heater maintenance skills. Beyond just your level of repair abilities, you do need to consider what type of furnace you are dealing with. Many modern, high-efficiency furnace models have an electric ignition tucked inside the unit that makes it difficult to access.

Troubleshooting why a furnace won’t ignite infographic

Troubleshooting: 4 Reasons Why a Furnace Won’t Ignite

If you’ve taken the necessary steps to ignite your furnace and it still won’t light, that could mean your furnace ignition is broken and needs to be replaced. Call us for quick furnace repair at (630) 788-4688. However, there are several different causes that could be keeping your furnace from lighting that a homeowner can check. If it’s one of these lesser issues, the work and cost of getting your heating system back and running could be easier and cheaper than needing a repair from a heating technician.

Here is a list of 4 items that homeowners can check before they call and pay for a service call. How much mechanical know-how you have may determine how many of these steps you feel comfortable doing yourself.

  1. Checking Thermostat to see if that fixes a furnace problemCheck your thermostat
    Set your thermostat to heat. The temperature needs to be at or above the current ambient temperature. Set the desired temperature up a few degrees. If you don’t feel heat coming from your vents shortly after doing this, you can eliminate this as the problem.
  2. Dirty filter coming out of a broken furnaceCheck your air filter
    It’s possible that a very dirty air filter could be preventing your furnace light from igniting. If the proper airflow isn’t happening, this could be restricting the pilot light from getting or staying lit.
  3. Check the circuit breaker
    The circuit to your furnace may have gotten tripped. If so, turn it off for a few minutes then reset it. Watch to see if it trips again. If so, you will need an HVAC technician to investigate what’s causing this problem. Request service from Maximum Heating & Air Conditioning and we will send a heating technician to your home for the repair your furnace needs.
  4. Check the gas line
    There is a switch inside or near the furnace that turns the furnace on and off. Make sure that it is set to the on position. Also, look for the gas valve and make sure it is not shut. If you have other gas-burning appliances, check if those are operating to verify whether the gas is on.

Furnace Ignites but Heat Still Not Coming on?

The good news is you eliminated one problem. The bad news is there are still other issues that could be causing your furnace to not work. Fortunately, there are more troubleshooting steps you can do with other components of your heating system.

One Easy Way to Avoid a Big Furnace Problem

Finding out your furnace isn’t working in the dead of a cold Illinois winter is the worst time. This is easily preventable. The first step in making that happen takes only a few seconds and you can do it RIGHT NOW!

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Put a reminder on your phone to turn on your heater on a full month before you expect to need it. For many of us in the Aurora area, that date might be in September.

This advice applies to your air conditioner as well. So, while you have your calendar open, go ahead and schedule a reminder to turn your air conditioner on sometime in the spring.

If you notice any problems with your heating or air before the worst of the season strikes, request service with Maximum Heating & Air Conditioning to have any problem resolved before you and your family are in need of your furnace or air conditioner working. We have a team of experienced HVAC technicians to best serve the Aurora area. Be sure to check out our page of deals and discounts to save money on the service that you need.

Call us at 630-788-4688

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