Finding the ignitor in a Goodman furnace is a common task for homeowners and technicians troubleshooting ignition problems. This article explains where the ignitor is typically located, how to identify different ignitor types, step-by-step inspection and replacement guidance, safety precautions, and troubleshooting tips to restore reliable heating. Understanding the ignitor location helps diagnose no-heat conditions and speeds repairs.
| Goodman Furnace Family | Typical Ignitor Type | Common Ignitor Location |
|---|---|---|
| Mid-efficiency Conventional (single-stage) | Hot Surface Ignitor (HSI) | Mounted near burner assembly, above or in front of burners |
| High-efficiency Condensing | Hot Surface Ignitor or Flame Sensor | Near secondary heat exchanger or burner throat |
| Modulating/Two-Stage | Hot Surface Ignitor or Spark Ignitor | Accessible behind burner access panel, sometimes under manifold |
How Goodman Furnace Ignitors Work
The ignitor provides the initial heat or spark to ignite the furnace’s gas. Most Goodman furnaces use a Hot Surface Ignitor (HSI) made of silicon carbide or silicon nitride that glows orange-white when energized. Some systems or older models use a spark ignitor. The control board supplies voltage to the ignitor only after safety checks such as the pressure switch and inducer fan operation complete.
Common Ignitor Types And Visual Characteristics
Hot Surface Ignitor (HSI)
HSIs resemble a small ceramic or wafer-like element with a short lead harness. They glow visibly when energized. Typical shapes include rectangular wafers, elongated rods, or blade-style elements. HSIs are fragile and often show visible cracks or missing ceramic when failed.
Spark Ignitor
Spark ignitors use high-voltage electrodes to create a visible spark. They are less common in residential Goodman furnaces but may appear in some models or retrofit units. Spark systems include an electrode pair positioned near the gas ports.
Where To Look: Typical Ignitor Locations In Goodman Furnaces
Goodman furnace layouts vary by model, but the ignitor is consistently located in proximity to the burner assembly and gas manifold. The most common access points are the burner access panel and the control access on the front of the furnace.
Access Panel And Burner Compartment
Most homeowners will find the ignitor behind the front panel labeled burner access or service panel. Removing this panel usually exposes the burners, gas valve, and ignitor. The ignitor is typically mounted on the burner box near the flame ports and secured with a single screw or clip.
Upflow, Downflow, And Horizontal Installations
In upflow furnaces the ignitor commonly sits at the top of the burner box. For downflow units the ignitor will be near the bottom portion of the burner compartment. Horizontal furnaces position the ignitor on the side of the burner assembly. Despite orientation, the ignitor remains adjacent to the burners for direct ignition.
High-Efficiency Condensing Furnaces
High-efficiency Goodman furnaces may have the ignitor located deeper in the burner throat or near the secondary heat exchanger to optimize ignition. These models can require removing additional panels or the burner box to access the ignitor and sometimes the flame sensor.
Step-By-Step: How To Locate The Ignitor Safely
- Turn Off Power And Gas: Before opening the furnace, turn off electrical power at the switch and shut off the gas supply. This prevents injury and unintentional ignition.
- Remove The Front Panel: Use a screwdriver to remove the screws securing the access panel labeled burner or service. Keep screws in a safe place.
- Identify The Burner Assembly: Locate the burner tubes and gas manifold. The ignitor will be near these parts, often inserted through a small mounting hole into the burner throat.
- Look For The Ignitor Element: Search for a ceramic wafer, rod, or blade with a two-wire harness. A spark ignitor will appear as a pair of electrodes near the burners.
- Trace The Wiring: Follow the two-conductor harness from the element back to the furnace control board or safety relay to confirm the component’s purpose.
How To Test An Ignitor
Testing the ignitor helps determine if it requires replacement. Only trained individuals should perform live electrical tests. Basic non-powered tests can identify obvious failures.
Visual Inspection
Examine the ignitor for cracks, breaks, or burn marks. HSIs are brittle; visible damage usually means replacement is necessary.
Resistance Check With A Multimeter
With power disconnected, unplug the ignitor harness and measure resistance across the ignitor leads. Typical HSI resistance ranges widely by model but often falls between 40 and 120 ohms when cold. A reading of infinite resistance indicates an open circuit and a failed ignitor.
Live Voltage Test
A qualified technician can verify voltage at the ignitor connector during the furnace start sequence. If voltage is present but the ignitor does not glow, the ignitor is defective. If no voltage exists, the issue may be control board or safety switches.
Replacing A Goodman Furnace Ignitor
Replacement is straightforward for many Goodman models. Homeowners confident with basic mechanical tasks can replace an ignitor, but power and gas must remain off during the procedure.
Parts And Tools Needed
- Correct OEM or compatible replacement ignitor (match model number or part number)
- Screwdriver or nut driver
- Multimeter for testing
- Work gloves and eye protection
Replacement Steps
- Power And Gas Off: Turn off power and gas to the furnace to ensure safety.
- Remove Access Panel: Unscrew the burner compartment access panel to expose the ignitor.
- Disconnect Harness: Unplug the ignitor connector from the wiring harness or cut ties as needed.
- Remove Mounting Hardware: Unscrew the mounting screw(s) or release clip holding the ignitor in place.
- Install New Ignitor: Handle the new ignitor by the base, avoid touching the element, align and secure it, then reconnect the harness.
- Test Operation: Restore power and gas, then run a short heat cycle to confirm the ignitor glows and the burners ignite correctly.
Troubleshooting Ignitor Related Issues
Ignitor Fails To Glow But Has Power
If the control board supplies voltage but the ignitor does not heat, the ignitor is likely failed. Replace with the correct part number. Verify harness integrity and connections to rule out wiring faults.
No Power To Ignitor
No voltage to the ignitor can be caused by a failed control board, tripped safety switch, open pressure switch, or blocked inducer motor. Check error codes on the furnace board LED and inspect components in the ignition sequence.
Ignitor Glows But No Ignition
If the ignitor glows yet burners do not light, problems may include a closed gas valve, clogged or misaligned burners, or a faulty gas valve manifold. Confirm gas supply and inspect the gas valve operation during the ignition sequence.
Maintenance Tips To Extend Ignitor Life
Proper maintenance can reduce premature ignitor failure. A few effective steps include keeping burners and the burner box clean, replacing air filters regularly to reduce furnace strain, and scheduling annual professional tune-ups. Preventive inspections catch early wear on HSIs and other ignition components.
When To Call A Professional
Electrical testing, gas valve repairs, control board replacements, and complex furnace diagnostics should be handled by certified HVAC technicians. Calling a pro is recommended if the ignitor tests normal but the furnace still fails to ignite, or if the homeowner is uncomfortable performing the replacement.
Replacement Cost And OEM Part Matching
Ignitor costs vary by model and supplier. Typical hot surface ignitors for Goodman furnaces range from $25 to $100 for parts. Labor can increase the total cost if a technician performs replacement. To ensure compatibility, match the part number printed on the old ignitor or consult the furnace model number and Goodman parts listings.
Safety Warnings And Best Practices
Always shut off electric power and gas before opening the furnace. Avoid touching the ignitor surface; oils from skin can cause hotspots and early failure. Dispose of failed ignitors properly and avoid forcing fragile ceramic components when removing or installing.
Key Diagnostic Checklist
- Power Off Before Service: Always disconnect electrical power and gas.
- Visual Check: Inspect for cracks, breaks, or discoloration on the ignitor.
- Resistance Test: Use a multimeter to check for open circuit.
- Voltage Check: Verify voltage during start-up (by a technician) if resistance is normal.
- Control Board Codes: Read LED flash codes for ignition-related faults.
Additional Resources And Parts References
Goodman service manuals and parts diagrams provide accurate locations and part numbers for specific models. Manufacturer documentation and reputable HVAC parts suppliers list replacement ignitors by furnace model. Local HVAC professionals can provide model-specific guidance and installation service.
For those troubleshooting at home, always refer to the furnace’s data plate for the model and serial number, then cross-reference that information with Goodman documentation or parts catalogs to identify the exact ignitor used in the unit.
If further help is necessary, contacting a licensed HVAC technician ensures safe, code-compliant repairs and reliable furnace operation.