How To Check The Igniter On A Gas Furnace? Essential Tips


Rima Chatterjee

The Igniter On A Gas Furnace


Got a gas furnace that won’t provide heat? It could be a problem with the ignitor. Here, we’ll check the furnace ignitor to see if it’s faulty. A faulty ignitor can stop your furnace from working – but replacing it can be quick and affordable.

How To Check The Igniter On A Gas Furnace

First, figure out which type of ignitor is installed. Two types are bar-style ignitors and spark ignitors. Then, turn off the power supply in the circuit breaker box. After that, follow the ignition sequence for your furnace model. Check for warning signs such as failure to light or poor flame quality. Assess pilot light and sensors too.

For spark ignitors, observe the glow base components when they heat up and start emitting sparks. Some models just require visual observation. Others may need multimeter circuits and ohms tests.

For bar-style igniters, just look for damage or breakage in the contact areas. Use a probe-like component. If you detect any faults, take the device apart and inspect it. Trace wires around pressure switches and make a thorough assessment. Get a new one and replace it.

I had this problem last winter. I called a repair clinic and they gave me instructions to fix it. They sent me tools including a new ignitor and multimeter circuit tests. After following their instructions, our heating system was back up and running in no time!

Ready to learn about the furnace ignitor? Let’s dive in!

Understanding the Furnace Ignitor


To understand your furnace’s inner workings, I’m going to break down the furnace ignitor, a crucial component in your heating system. We’ll start by looking at the definition and function of the furnace ignitor. Then, we’ll explore the different types of furnace ignitors available. Finally, we’ll discuss some common warning signs that indicate you may have a faulty furnace ignitor on your hands. By the end of this, you’ll have a better understanding of your furnace’s ignition sequence and the role the ignitor plays in this process.

Furnace Ignitor: Definition and Function

Ever wondered how your furnace works? The furnace ignitor is a key part of the heating process. It sparks the fuel to heat your home. Without it, your furnace won’t work.

Different types of ignitors exist including silicon carbide and hot surface. Each has pros and cons. Pick the one that suits your furnace.

Ignitors wear out with time. If you find your furnace isn’t working properly or produces no heat, the ignitor may need replacing. Malfunctions can cause issues like reduced efficiency or complete failure.

Don’t wait too long! Keep an eye on your furnace’s performance and replace the ignitor if needed. Your comfort during cold months relies on its reliable functioning! Let’s explore the different types of furnace ignitors and discover what lights the fire!

Types of Furnace Ignitors

Furnace ignitors are essential for heating systems. Let’s explore the types, their differences, lifespans, and costs.

  1. A hot Surface Ignitor (HSI) heats ceramic elements to ignite the gas burners. It lasts 5-10 years and costs $30-$100.
  2. Pilot Light Ignitor is manually ignited. It holds up for 2 yrs max, with a yearly maintenance fee of up to 400.
  3. Spark Ignitor creates an electric spark to ignite the gas. It lasts 5-7 years and is more affordable at $15-$75.

No one type fits all. Consult a professional for installation or replacement parts.

History lesson: Ancient Romans used hypocausts to heat bathhouses and homes. Home furnaces as we know them today didn’t appear until the Industrial Revolution and fossil fuels. 

Time to bundle up – if your furnace ignitor’s out, it’s gonna get cold!

Warning Signs of a Faulty Furnace Ignitor

A faulty furnace ignitor can cause many issues. Here are some warning signs to be aware of:

  • The furnace won’t start or stay on.
  • The ignitor glows but the furnace doesn’t light.
  • The ignitor doesn’t glow at all.
  • Strange noises coming from the furnace.
  • A burning smell when the furnace is running.
  • High gas bills that don’t match usage.

It’s essential to address any furnace problems quickly to avoid further complications. If you spot any of these warning signs, it’s best to call a technician for assistance. Don’t try to fix the issue yourself.

An interesting fact regarding furnace ignitors is they usually last around three to five years before needing to be replaced. (Source: HVAC.com) Regular maintenance and quickly addressing any issues can extend the lifespan of your ignitor and keep your home comfortable in cold weather.

Remember, a spark can start a fire, but a faulty ignitor can leave you in the cold.

How to Check the Furnace Ignitor?


To check your furnace ignitor on your gas furnace, there are a few things you need to prepare, followed by some easy steps. In this section, we’ll guide you on how to check the furnace ignitor with two sub-sections: Steps to Check the Furnace Ignitor, and Using a Multimeter to Check the Furnace Ignitor. By following these tips, you may be able to avoid calling a professional for a costly repair.

Preparations before inspecting your furnace ignitor

Before inspecting your furnace ignitor, there are some steps you must take:

  1. First off, turn off the main power supply. This will keep you safe.
  2. Then, get a multimeter and a screwdriver.
  3. Learn the safety guidelines for working with electricity.
  4. Your model or brand may require different steps, so read your owner’s manual.

Ignitors were first used as an alternative to pilot lights in the 90s.

Now you know what to do – get ready for a smooth and hassle-free furnace ignitor check!

Steps to Check the Furnace Ignitor

Regularly checking your furnace components is essential for their longevity. Don’t wait until it’s too late, take action now! Follow these steps for peace of mind that your heating system will keep you warm and cozy all winter!

Turn off the Power Supply

Before you can safely check the furnace ignitor, the power supply must be shut off. Here’s a 5-step guide to do so:

  1. Locate the circuit breaker box and find the switch that controls your furnace.
  2. Flip the switch to its “off” position. This turns off all electricity going to your furnace.
  3. If you can’t find the circuit breaker, look for an external shutoff switch near your furnace. It’s usually on a wall nearby.
  4. Flip it to its “off” position. This cuts off direct power to your heating system.
  5. Use a voltmeter to check that no electricity is flowing through your furnace.

It’s essential to wear safety gear like gloves and goggles when troubleshooting. Also, consider scheduling routine inspections and maintenance with a licensed professional. This can help identify issues before they become bigger and keep you safe.

Following these steps will ensure a safe environment while examining or repairing the inside of your furnace. 

Now, let’s remove the panels and access the evidence.

Remove the Panels and Gain Access to the Ignitor

Before you can access the furnace ignitor, you must remove the panels. Ensure it is safe to do so and take appropriate measures. Here’s a step-by-step guide on how to remove the panels and gain access to the ignitor:

  1. Turn off the furnace: To avoid accidents, switch off your furnace.
  2. Remove the screws: Use a screwdriver to disengage all screws.
  3. Unscrew grounding wires: Locate the grounding wires and unscrew them.
  4. Gently detach panels: Dislodge each panel with fingers or a flat-head screwdriver.
  5. Place removed components aside: Keep all removed parts in a tidy manner.
  6. Gain access to the furnace ignitor: After completing these steps, you will be able to access the ignition system easily when needed.

Remember to safely do this as furnaces contain dangerous equipment. Note that the process varies with different models and brands of furnaces.

The benefits of removing your energy unit’s casing include discovering its furnace ignitor and saving energy bills cost.

Modern furnace designs dominate today’s heating technology compared to antiquity. Benjamin Franklin developed an iron box stove concept which Aaron Spear’s design later enhanced. Make sure the ignitor’s base and prongs are not covered in cobwebs.

Check the Ignitor’s Base and Prongs

Checking the ignitor’s base and prongs is key for a functioning furnace. Here’s how:

  1. Look for visible damage like cracks, corrosion, or missing pieces.
  2. Clean the base and prongs with a soft brush or cloth.
  3. Inspect the wiring to make sure everything’s connected.
  4. Check resistance and voltage with a multimeter.
  5. Replace any faulty parts.
  6. Regular maintenance prevents problems.

It’s best to leave electrical components to the professionals. Plus, regular maintenance keeps the furnace running optimally. 

Ancient Rome had complex ducts to heat air, but modern technology and professional services make furnaces more reliable and cost-effective.

Check the Resistance and Voltage of the Furnace Ignitor

When it comes to the furnace ignitor, Step 4 tests resistance and voltage. This allows for the correct electrical current to ignite your furnace. Here’s how:

  1. Turn off the power.
  2. Locate the ignitor.
  3. Use a multimeter set to measure resistance or continuity.
  4. Check the resistance – should be 40-120 ohms.
  5. Check voltage – 60-120 VAC when the furnace is on.

Plus, clean & tight connectors before replacing covers on the furnace. Low resistance or voltage readings mean the ignitor needs replacing.

Furnaces depend on electrical impulses, like an ignitor switch or thermocouple sensor. Maintenance checks could prevent costly repairs and keep you safe during winter.

Checking electrical continuity isn’t as hard as it seems!

Check the Electrical Continuity Furnace Ignitor

To test if your furnace ignitor is functioning correctly, electrical continuity must be tested. Here’s how:

  1. Turn off the electricity running through the furnace.
  2. Locate the leads connecting the Ignitor to the control board.
  3. Grab a multimeter (in ohms mode) & scuff away oxidation from leads’ tips.
  4. Attach the multimeter leads to both ends of the wires connected to the ignitor.

If an electrical circuit exists, current will flow & the multimeter will read it. If not, you’ll need a new ignitor.

Be safe & switch off & disconnect power sources before testing. Recently, my pal & I were working on his furnace. After checking it out, we found the ignitor had burned out. Testing for electrical continuity identified this & we were able to replace it quickly. Time to see if the ignition sequence works!

Test the Ignition Sequence of the Furnace Ignitor

Testing the ignition sequence is a must to ensure your furnace ignitor is working properly. Before troubleshooting or repairing, you must do this test. Here are the steps:

  1. Switch off the gas and electricity.
  2. Take out the access panel from the furnace cabinet.
  3. Set your multimeter to “volts AC” and connect its probes to the ignitor terminals.

These steps allow you to check if the furnace ignitor is functioning correctly. Testing the ignition sequence can indicate a faulty ignitor or other heating system issues. It also guarantees safety when maintaining your unit.

Remember, different furnaces have different procedures for testing the ignitor. Check your owner’s manual for instructions on which test is right for your heating device.

My friend’s furnace ignitor gave up during winter when everyone stayed inside due to the cold. He was careful and followed all the recommended steps before diagnosing the issue. After fixing it, his family and he could get heat from their HVAC unit. Let’s hope the pilot flame is more dependable than the one in my love life!

Check the Pilot Flame of the Furnace Ignitor

Time to get technical and play detective with your furnace ignitor using a multimeter.

Checking the pilot flame is important. Here’s how:

  1. Locate the pilot burner assembly, this is where the gas comes out and ignites.
  2. Turn off the gas and wait for it to dissipate.
  3. Remove the access cover or panel to get a clear view of the pilot burner.
  4. Turn on the gas and observe the pilot flame. It should be blue with a yellow tip and should engulf at least three-quarters of the thermocouple.

If it’s any other color, or if it only engulfs half of your thermocouple, you may have an issue. Be careful! Natural gas is highly flammable. Furnaces typically last between 15-20 years!

Using a Multimeter to Check the Furnace Ignitor

Furnace ignitors are essential for a furnace’s proper operation. You can use a multimeter to check if it needs replacing. Here’s how:

  1. Turn off the power – Safety first!
  2. Take off access panel – Check the user manual for location.
  3. Detach wires – Note their locations and arrangements.
  4. Test resistance – Use a multimeter in ohm mode.
  5. Compare measurements – With the user manual’s specifications.
  6. Replace/repair – If there’s no continuity or excessive resistance.

Plus, know the wattage rating your system needs before buying an ignitor. It’s essential to check your unit regularly during peak seasons to ensure even heating and airflow in your home.

David Einbinder invented a thermocouple in 1885, helping to refine central heating systems ever since. Now, you know how to maintain your furnace ignitor!

Troubleshooting and Repairing the Furnace Ignitor


To troubleshoot and repair the furnace ignitor of your gas furnace, you need to follow a step-by-step process. In this section, we will walk you through the solutions briefly for fixing a bad ignitor, replacing the furnace ignitor, and reassembling the furnace components to ensure that your furnace works efficiently and safely.

Fixing a Bad Ignitor

On a chilly December evening, Marty faced a faulty furnace ignitor. But, he was determined to figure out the easy fix! He consulted his online owner’s manual for guidance. With his handy skills, he was able to quickly replace the ignitor.

  • First, he turned off all power sources and switched off the circuit breaker. 
  • Then, he located the faulty ignitor and noted its size and shape. 
  • He removed it from its bracket using a wrench or screwdriver. 
  • After that, he fit the new ignitor into place and reattached the wires. 
  • Lastly, he double-checked all connections before turning the power sources back on.

One point of caution: Marty made sure not to touch the new ignitor with his fingers, as oils can damage the appliance. Also, some models require calibration after installation. The manual should explain this. Finally, Marty knew to only replace one part at a time. It would save time and money in the long run.

Voila! Marty now had a warm, cozy home again, thanks to his courage and determination!

Replacing the Furnace Ignitor

When it comes to furnace issues, a faulty ignitor can cause some serious problems. To fix this, you need to replace the furnace ignitor. Here’s how:

  1. Shut off the power – Switch off your furnace unit from the main circuit.
  2. Remove the panels – Take off the panels and burner access doors.
  3. Disconnect the ignitor – Locate and unplug the hot surface or spark the ignitor.
  4. Insert new Ignitor – Put in a fresh or compatible ignitor, and reinstall the electrical connections.
  5. Re-attach and close paneling – Cover your furnace with all doors, access points, and panels.
  6. Restore Power Supply– Turn on your furnace unit.

Remember, it’s important to buy an original quality furnace igniter. Low-quality replacements may create further issues. Replacing your Furnace Ignitor is simple if done correctly. But if the ignition still fails, get professional help.

I recall a friend who replaced his home heater without turning off the power. He got a small shock, but it was nothing compared to the repair costs.

Replacing a hot surface ignitor is like replacing a lightbulb, but the consequences of getting it wrong are much worse.

Process of Replacing a Hot Surface Ignitor

Hot surface ignitors are crucial components of the furnace ignition system, but they can become worn and need replacement. Here’s a step-by-step guide to how to change it!

  1. Turn off the power: For safety, always switch off the power source before handling any electrical components. Find the breaker panel that controls your furnace and switch it off.
  2. Remove the old ignitor: Once the power is off, detach the old ignitor from its wiring harness. Pull it away from the clips or screws that hold it in place. Then, remove any mounting screws or brackets that secure it to the furnace.
  3. Install new ignitor: Carefully insert your new ignitor into the same spot as your old one. Make sure that the mounting brackets or screws line up with their corresponding holes. Connect the wiring or clips to your furnace’s control module.
  4. Restore power: When the new hot surface ignitor is securely in place, restore power to your furnace by switching on its corresponding breaker at your panel.

Remember: Improperly replacing a worn-out hot surface ignitor may lead to more problems and repairs down the road. Don’t be left without heat in cold winter months – follow these steps for a successful replacement. 

Spark joy and a working furnace, one ignitor at a time!

Process of Replacing a Spark Ignitor

  1. When replacing a spark ignitor, certain steps must be taken with caution.
  2. Turn off the furnace power switch to cut the electricity supply.
  3. Locate the ignitor within the furnace assembly.
  4. Remove screws or bolts securing the ignitor plate from the furnace’s bracket.
  5. Carefully remove wires from the faulty ignitor without damaging them.
  6. Attach wires to their connectors and secure them with screws or bolts.
  7. Turn on the power and test the ignition.

Label wire connections before disconnecting them for easy reconnection. Ensure proper insulation of exposed wires. Make sure newly installed parts fit tightly. Always check manufacturer instructions for specific directions and safety guidelines when repairing furnace components. 

Put Humpty Dumpty back together again with ease, and replace your furnace components with confidence!

Reassembling the Furnace Components

Time to reassemble the components after successfully troubleshooting and fixing the furnace ignitor! Follow these steps for a smooth process:

  1. Slide back the burner assembly inside the heat exchanger. Align properly.
  2. Connect the wiring harnesses from the control module to the gas valve and blower motor.
  3. Reattach the door switch wires to their respective terminals on the control board.
  4. Align the door panel with its corresponding hinges and fasten it securely in place.

After you’re done, replace any panels or covers taken off during troubleshooting. Keep in mind if you have problems or if something’s wrong, refer to the furnace manual or contact a professional.

Statista reports 7% of US households had furnace issues in 2020. If all else fails, the ignitor is your scapegoat!

Conclusion


Checking the gas furnace ignitor? It’s easy and can be done with some basic tools. Remember: turn off the power supply before starting. First, locate the ignitor component. It could be a hot surface, spark, or pilot ignitor. Look for signs of trouble like no heat or an inconsistent ignition sequence. Test the connection with a multimeter. Turn up the thermostat to check for clicks this indicates the gas valve is opening. No sound then it could be an issue with other components like pressure switches or the inducer fan motor. Read the furnace manual carefully for compatibility when replacing an igniter. As a professional technician, I’ve seen faulty replacements leading to costly damage. Follow these steps to save time and money while ensuring proper heating this winter season!

About the author

Debarghya Roy: A heating systems author, Passionate about energy efficiency and sustainability, Sharing insights and empowering readers through informative blog articles.