Furnace Ignitor Replacement Cost Guide

The cost to replace a furnace ignitor varies widely based on ignitor type, furnace model, and whether a homeowner hires a professional. This guide explains typical price ranges, factors that influence cost, DIY considerations, and tips to minimize expenses while ensuring safe, reliable heating. Key takeaway: most replacements range from $75 to $400, with common ceramic hot surface ignitors usually costing $150 to $300 installed.

Ignitor Type	Parts Cost	Labor Cost	Typical Installed Cost
Hot Surface Ignitor (HSI)	$40–$150	$80–$200	$120–$350
Intermittent Pilot / Spark Ignitor	$15–$75	$60–$150	$75–$225
Flame Sensor Replacement	$10–$50	$60–$120	$70–$170

What Is A Furnace Ignitor And Why It Matters

A furnace ignitor is the component that initiates combustion inside a gas furnace by producing heat or a spark to ignite the gas burner. Common types include hot surface ignitors (HSI), which glow red-hot, and spark or intermittent pilot ignitors, which generate a spark to light the pilot or burners. A failed ignitor prevents the furnace from heating and can cause repeated lockouts or unsafe conditions.

Typical Furnace Ignitor Replacement Cost Ranges

Replacement costs depend on part price, labor rates, and regional variations. The following ranges reflect typical U.S. pricing:

• Hot Surface Ignitor (HSI) Installed: $120–$350. HSIs are common in modern furnaces and are more expensive to replace.
• Spark/Intermittent Pilot Ignitor Installed: $75–$225. Less complex and generally cheaper.
• Flame Sensor Replacement Installed: $70–$170. Often replaced together with ignitor if corroded or faulty.

Factors That Influence Replacement Cost

Several variables determine the final price. Understanding these helps homeowners estimate costs more accurately.

Ignitor Type And Quality

OEM (original equipment manufacturer) parts cost more than aftermarket components. HSI parts from brand-name manufacturers typically run higher due to fit and reliability assurances.

Labor Rates And Service Call Fees

Technician hourly rates vary by region and company. A minimum service call fee often covers diagnostics; expect higher labor costs in urban centers. Typical HVAC labor ranges from $80 to $150 per hour depending on complexity and location.

Furnace Accessibility And Complexity

If the ignitor is hard to reach because of furnace layout or additional disassembly, labor time increases. Older furnaces or compact units may require extra steps, adding to cost.

Warranty And Additional Repairs

Warrantied parts can lower out-of-pocket costs if still covered by manufacturer or installer warranty. Technicians may recommend replacing related components like the flame sensor or control module, which raises the total cost but can prevent repeat service calls.

How To Diagnose A Bad Furnace Ignitor

Accurate diagnosis prevents unnecessary replacements. Technicians use a multimeter to test continuity and may observe the ignition sequence. Common signs of ignitor failure include repeated furnace lockouts, the furnace trying to light but no burner ignition, and visible cracks or breaks in HSIs.

Quick Checks Homeowners Can Do

• Listen for the startup sequence: transformer hum, gas valve click, then ignition attempt. If ignition never occurs, an ignitor issue is likely.
• Inspect the ignitor visually for cracks or breaks when power is off and the furnace is cooled down.
• Replace the furnace filter and ensure sufficient airflow—sometimes poor airflow causes safety systems to inhibit ignition.

DIY Replacement: Pros, Cons, And Safety

Homeowners with mechanical experience can sometimes replace ignitors themselves to save on labor costs. However, safety and warranty considerations are key.

Pros

• Parts-only cost can be significantly lower.
• Quick turnaround if part is available.

Cons And Safety Considerations

• Risk of electrical shock and gas-related hazards if safety protocols are ignored.
• Incorrect installation can damage the furnace or void warranties.
• Some furnaces require calibration or control board resets after replacement.

Only attempt a DIY replacement if comfortable with electrical systems, gas appliances, and following manufacturer instructions. Always turn off power at the breaker and shut off the gas supply before working on the furnace.

What To Expect During A Professional Replacement

A licensed HVAC technician typically performs the following steps: diagnose the ignition system, order the correct OEM or compatible part, power down and safely access the furnace interior, remove and replace the ignitor, test the ignition sequence, and confirm safe operation. A standard service call often includes minor adjustments and a short operational check.

Ways To Save On Replacement Costs

Smart strategies can reduce expenses while maintaining safety and reliability.

• Shop For Multiple Quotes: Compare 2–3 reputable HVAC companies for pricing and service inclusions.
• Use Aftermarket Parts Carefully: Quality aftermarket ignitors can be cheaper, but verify compatibility and warranty terms.
• Bundle Repairs: If the furnace is old or several components are worn, combining repairs into one service visit may reduce total labor costs.
• Maintenance Plans: Annual tune-ups can catch wear before failures; some plans offer discounts on parts and labor.

When Replacement Is Preferable To Repair

Replacement is recommended when ignitors are cracked, show no continuity, or the furnace experiences frequent ignition failures. In older furnaces, repeated failures and obsolete parts may indicate it is more cost-effective to consider furnace replacement rather than repeated repairs.

Typical Lifespan And Warranty Expectations

Hot surface ignitors typically last 3–7 years depending on usage and operating conditions. Spark ignitors and flame sensors can last longer but are susceptible to corrosion and soiling. Many replacement parts carry limited warranties of 90 days to one year from independent suppliers; OEM parts may carry longer warranties through the manufacturer.

Red Flags To Watch For After Replacement

After installation, homeowners should monitor the furnace for normal startup cycles, even heating, and absence of repeated lockouts. If the furnace trips the safety switch, emits odd smells, or shows irregular flame patterns, shut the unit off and contact the installer immediately.

Cost Examples By Scenario

Scenario	Parts	Labor	Total
HSI Part Replaced In Suburban Area	$70	$120	$190
Spark Ignitor Replacement In Urban Area	$30	$100	$130
HSI Plus Flame Sensor Replacement	$95	$160	$255

How To Find A Reliable HVAC Technician

Choose licensed, insured HVAC contractors with positive reviews. Verify licenses and check for Better Business Bureau ratings. Request a written estimate detailing parts, labor, warranties, and any service call fees. Ask whether the technician carries parts compatible with the furnace brand and model.

Frequently Asked Questions

Can A Furnace Work Without An Ignitor?

No. A functioning ignitor is essential for gas furnaces to light the burners. Without it, the furnace will not produce heat and will likely go into safety lockout.

How Long Does A Replacement Take?

Most ignitor replacements take 30–90 minutes, depending on furnace access and whether additional parts are needed. Diagnostic time may add to the service call length.

Is It Safe To Run The Furnace With A Faulty Ignitor?

Running a furnace with an unreliable ignitor can lead to repeated gas valve cycling and safety lockouts. It is not advisable; contact a professional for prompt repair.

Will Replacing The Ignitor Improve Heating Efficiency?

Replacing a failed ignitor restores normal operation but does not significantly improve efficiency. Efficiency gains typically come from regular maintenance, sealing ductwork, or upgrading to a higher-efficiency furnace.

Checklist Before Scheduling Replacement

• Note furnace brand, model, and serial number for correct part matching.
• Record error codes or observation of the ignition sequence for technician reference.
• Clear access area and ensure safe entry for service personnel.
• Ask for an itemized estimate including parts, labor, trip fees, and warranty details.

Final Recommendations

When an ignitor fails, prompt replacement prevents extended downtime and potential safety issues. For most homeowners, hiring a licensed technician ensures proper diagnosis, safe installation, and warranty protection. Compare quotes, consider OEM vs aftermarket options carefully, and prioritize safety and reliability over minimal upfront savings.

Useful Resources: Consumers can reference manufacturer manuals for part numbers and the U.S. Department Of Energy for furnace maintenance tips. Always follow local codes and regulations when servicing gas appliances.