How To Tell If An Ignitor On A Gas Furnace Is Working

gas furnace that isn't working properly

If you have a gas furnace, a common problem that you will probably encounter is electronic ignition failure. It is important that you know how to identify when your gas furnace ignitor not working so you know whether or not the problem will require the services of an HVAC contractor.

Explore Our Heating Repair Services Call To Schedule A Free, In-Home Estimate

Is Your Gas Furnace Ignitor Not Working Properly?

If the problem with your furnace ignitor is simple enough, you could perform simple troubleshooting steps to understand why your ignitor is acting up. You can then decide when to call a professional HVAC technician for a furnace repair.

What Are the Types Of Furnace Ignition Systems?

gas furnace flames

Older furnaces had built-in pilot lights that remained on while the unit is working. In this type of heating system, gas valves that lead to the burners open to ignite the combustible gas. In situations where pilot lights fail, the heater will stop working as well.

Newer models, on the other hand, have electronic ignition systems. These systems may run on hot surface ignition or intermittent pilot.

With the intermittent pilot system, an electric spark turns on the pilot light. A sensor detects if the pilot light is active and will open the valve that leads to the burners. The pilot light then ignites these burners. In a hot surface ignition system, electricity flows to the ignition until it reaches a pre-set temperature. When this happens, gas will flow to the burner. This will light up the ignitor.

These systems both turn the pilot light off when the furnace is turned on. This is why newer systems have a higher energy efficiency compared to older systems.

Call Today: (610) 377-1098

What Happens When An Electronic Ignition Fails?

feeling chilly due to malfunctioning heating system

Furnace ignition failure happens when the ignition does not work. This means that it will not be able to ignite the burners, which in turn will not generate heat.

There is another type of problem-related to furnace ignition failure and this is delayed ignition. This is fairly easy to detect because the furnace system will usually produce a loud bang before it ignites.

The loud sound occurs due to the accumulation of gas when the ignitor is turned several times in succession. The problem with this is that it poses a safety issue for your home which could potentially be serious or even life-threatening. If this happens, call your local HVAC technician right away.

Explore Our Furnace Repair Services Call To Schedule A Free Estimate

Why The Gas Furnace Ignitor Stops Working

Let’s take a look at the different causes of ignitor problems.

Damaged Ignitor

With regular use, the ignitor can become worn down or damaged. When this happens, it has to be replaced by a professional. You might want to consider having your furnace checked by your HVAC technician first to determine if it does have a damaged ignitor. The technician will remove the service panel of the furnace and inspect it for any damage. He will likely remove the ignitor wires and test the ignitor using a multimeter.

Mismatched Ignitor

Using the wrong ignitor that has a mismatched voltage can cause the ignition to fail.

High-Temperature Limit Switch

Your furnace is built with a limit switch to prevent extremely high temperatures in the unit. The most common cause of high temperature in the limit switch is a clogged air filter. A mechanical issue with the limit switch will also cause the ignitor to fail.

Power Surges

Power surges are notorious for causing damage to the electric ignitor. Sudden surges in power can burn out the filaments in the ignitor.


Furnace Ignitor Troubleshooting Tips

If you notice a problem with your heating system, it is possible to check the unit yourself to determine if the issue can be fixed easily. Here are a few troubleshooting tips you can do:

Do A Power Check

If there is no power to the unit, it may be because the circuit breaker was tripped. Check the source of power to determine if this is the problem with the heating system.

Reset The Ignitor

First, turn off the furnace. Switch off the circuit that delivers power to the furnace. Look for the burner door and open it. Behind it, you will find the ignitor. Turn it off for 5 minutes, then turn it back on. After ensuring that the door switch has been engaged correctly, close the burner door. Turn on the furnace again by switching the power at the main electrical panel.

Call To Schedule A Free Consultation


Having More Issues? Why You Should Call An HVAC Professional

Any issue with your heating system must be checked and analyzed by a professional HVAC contractor. Their technicians are trained in the correct approach required to identify and assess the problem and apply the proper solution. A professional can ensure that the furnace is assessed correctly to eliminate any risks to your home and safety.

Should you try to fix the problem yourself? It may be tempting to because you might think it’s a quick, easy, and cheap fix, but keep in mind that the furnace is a specialized type of equipment. If you do not know what you are doing and have very little to zero understanding about how the system works, it is far safer for your home and yourself to leave the repairs to a professional.

DIY repairs are not recommended for sensitive equipment such as furnaces. If you do not know what to do, you can do more damage to the unit and end up paying more for repairs and replacements. It is far better to have your furnace checked by a professional than attempt the repair on your own. You can save on time and cost by doing so.

Click To Schedule An Appointment Now!



Problems with the ignitor are fairly common and they could either be simple or more complicated for you to handle on your own. It may not always be as basic as having an old ignitor replaced. Electronic ignitors, for example, are not lit manually. Even if it is as simple as a clogged filter that has to be cleaned or replaced, you would still need a professional to do the job properly and safely.

The reason why you need to learn a few troubleshooting steps is so that you will understand how your furnace works. Having the right information will also help you discuss the problem with your HVAC contractor. If you want a professional solution, make sure to contact a local HVAC technician.

Call R.F. Ohl For Professional Furnace Services

RF Ohl logo
When you need a professional solution, call R.F. Ohl for advice. We are the leading heating and cooling services provider in the area. Our certified technicians are trained and experienced in performing HVAC tune-ups, installations, replacements, and repairs. We provide the most competitive services that ensure a careful approach so that your comfort and safety are prioritized. Call R.F. Ohl today for your free in-home estimate.
Call Now: (610) 377-1098 Explore Our Case Studies

Click here to contact us today or give us a call at (610) 377-1098 if you have any questions.