How To Tell If Your Furnace Ignitor Is Bad (With Solution and Buying Guide)

How to tell if your Furnace Ignitor is Bad

In today’s day and age, there is no facing harsh summers or winters without modern convenience appliances. Why should you, after all, when cheap and affordable heating and cooling gadgets with high-powered technology are right at your disposal.

Why would you willingly subject yourself to cold, freezing nights in winter when you can get a heater or a furnace and make your life better. 

But modern technology is not without its pitfalls- it’s not perfect, and so you might find yourself waking up this winter with your furnace not acting up to the standards you were promised.

A broken furnace can ruin your whole day, and you want to take preventive measures to ensure that doesn’t happen to you. 

You might have great intuition, maybe your gut is telling you, you simply have to go take a look at your furnace because the energy is off. Or maybe you’re like the rest of us normal folks who need a little help, which is why we’re going to cover the art of identifying the symptoms of a bad furnace.

For this, you’d have to look at the ignitor, as it’s what triggers the furnace to heat up. These tips below should help you tell if something is off with your furnace ignitor.

Signs Of A Faulty Furnace Ignitor And Things You Must Check

There are a variety of aspects to look at if you’re considering that something might be wrong with your furnace ignitor. 

The Furnace is blowing Cold Air

Of course, one of the first noticeable signs of a faulty furnace ignitor unit is that it’s failing at its job- it’s not heating up the room as it should. It’s not sending warm air your way. Instead, if you’re getting cold air, you might want to check up on these parts:

Check Your Thermostat

Make sure that it is running at a higher temperature than the room temperature. That is, if your room is at 60F in temperature, ensure that your furnace is set at a higher 68 F temperature. 

Also, if your furnace has a heating and cooling option, check if your thermostat is set to heat. If all is good with the Thermostat, chances are you need to be addressing some other part of your furnace. 

Check Your Inducer Motor

The inducer motor makes sure that harmful and dangerous exhaust fumes are vented out through the chimney. By doing this, creates a vacuum,  and leaves space for fresh warm air to be sent out into the room.

Ideally, the first part of your furnace that should switch on is the inducer motor. If you don’t hear it revving up, you know where the problem lies. 

However, if there’s no problem detected, you might want to consider calling in a technician to look at the thermostat, the draft inducer motor, the control board, or the pressure switch to figure out some deep-rooted issue that you can’t seem to find externally. 

The Power SWITCH

If your furnace doesn’t come on, you might want to check the breaker box. If the switch connected to your furnace isn’t tripped towards “On”, it’s simply a matter of turning the switch on. You might also want to trace the furnace back to the main power line that controls it and check if that switch I turned on as well. 

Clogged Air Filter

If your furnace ignitor stops firing up your furnace suddenly, you should check with the air filter. Much like in an air conditioner, an air filter purifies and keeps the air clean both inside and outside the furnace.

However, if the air filter is blocked by dust and debris and is clogging up, it might prevent the warm air from flowing out properly. Like any appliance, proper maintenance of your unit will ensure that you don’t run into these problems often. 

Check Your Return Vents

Another place to check when you’re facing this issue is the Chimney vent. More than often you’re probably just running into practical problems like the chimney vent being blocked by an animal or thing, or maybe ice or soot.

This holds back the furnace from working as there’s no vacuum that can be created. If a vacuum can’t be created to exhaust air out, this can be dangerous, so the pressure switch will most probably automatically switch off the unit. 

Constant Tripping Breaker

Checking the breaker switch is already something you should have done when if you’re facing a faulty furnace. If the breaker, however, trips to “Off” often, then your furnace ignitor is really not working up to the mark.

In fact, repeated breaker trips can be dangerous, so we recommend that you get that checked by an electrician as soon as possible. If the furnace ignitor clicks, but the furnace doesn’t start up again, this is indicative of a faulty furnace ignitor. 

There are ways to inspect your Ignitor specifically if that’s where your issue lies. In fact, the ignitor is considered to be quite a quick and easy fix, so we think that you might be able to play technician and repair it yourself with some help from the internet. 

Once you’ve established that your furnace is safe to touch, open it up through the little burner panel. Then, you’ll find a small device between all the electric wires- this is your Ignitor. Your Ignitor is a device with two metal prongs and a ceramic base, so re-check that you’re not messing with the wrong component. 

Reasons Why Your Furnace Ignitor might be Causing Problems:

  • If your Ignitor has an incompatible limiter switch, it might be turning off the unit sooner than it needs to. A faulty limiter switch can misread the temperature and perceive the ignitor to be running hotter than it is. This led to the heater being switched off before it can efficiently warm the room. 
  • If you’ve recently replaced your Ignitor, then you’re probably dealing with an Ignitor that’s simply a wrong fit for your unit. 
  • Or, the opposite might be the case, if you’ve been using your Ignitor for a long time, it might have exceeded its lifespan, and it is probably time to replace it with a new one. 
  • If your Ignitor doesn’t show any cause for concern and is yet messing with the working of your furnace, it’s time to resort to a technician. We recommend you do this even if there’s technically not a problem with your Ignitor, but if it’s still over 7 years old, as it’s probably due for a replacement. 

Furnace Ignitor Buying Guide

Cost of Replacing your Furnace Ignitor

Replacing a Furnace Ignitor can draw quite a hefty sum of money from your pocket. If you ring up a Furnace company to help you, they might charge you as much as $70-200, most of which is just because of the service fee that is standard for a company to charge. 

If a replacement is an absolute emergency, and you’re unlucky enough for it to have happened during non-business hours, the furnace ignitor cost of replacement can even go up to $300. 

However, if a furnace ignitor replacement is not a need of the hour, we recommend that you try to handle it yourself. This will not only save you money but also time, with the part costing no more than $15. 

Where should you buy a Furnace Ignitor?

It’s not hard to find a Furnace Ignitor part in local hardware or repair shops. Moreover, if you require one of the popular kind, the search might be easier.

In fact, it would probably help if you simply took your furnace ignitor with you, and referred it to your hardware supplier at the local store. They’ll know exactly what you’re looking for if you’re not sure yourself. 

But you don’t have to limit yourself, online hardware stores and HVAC parts stores are places where you’re bound to get a great deal and more options. Typically, furnace ignitors of the Universal replacement types work for everything. But you can also search by brand name. 


If your furnace is giving you trouble, your Ignitor is one of the main parts you should check by following the tips listed in this article. This is especially true if you own an old or worn-out ignitor model that needs replacing. And if you need a replacement, surely refer to the buying guide so you know how, when, and where to start looking for a furnace ignitor part for your furnace. 

Related: Also Check Our Complete Furnace Repair Guide

Related: Check and Replace Your Furnace Ignitor

Related: Best Gas Furnace review and Price Analysis

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