How long does a furnace igniter last?
Updated August 2026
A hot-surface furnace igniter lasts 3–7 years, one of the shortest-lived parts in the whole heating system. It works by glowing red-hot to light the gas on every call for heat, and that repeated thermal shock is exactly what wears it out. Newer silicon-nitride igniters run toward the top of that range, while the older, more brittle silicon-carbide type sits near the bottom. The part itself is cheap at $15–70, but a service call to install one usually brings the total to $150–350.
Lifespan by type and situation
| Type or situation | Typical lifespan | Why |
|---|---|---|
| Silicon-nitride igniter | 5–7 years | The modern, sturdier type; flat or spade shaped |
| Silicon-carbide igniter | 3–5 years | Older, brittle, fork shaped; cracks easily and burns out sooner |
| Furnace that short-cycles | Cut 1–3 years | Every ignition is a heat shock; more cycles, shorter life |
| Touched by bare hands | Fails early | Skin oil creates a hot spot that cracks the element on the next firing |
| Dirty flame sensor forcing retries | Shortened | Repeated failed light attempts hammer the igniter with extra cycles |
Signs yours is near the end
- The furnace blower runs but no heat comes out, the classic no-ignition symptom
- You hear the igniter click and the gas valve open, but nothing lights
- A visible crack or a clean break in the igniter element on inspection
- The igniter no longer glowing bright orange, or not glowing at all
- The furnace taking several tries to light, then locking out after three attempts
How to add years
An igniter is a wear part, so the goal is fewer, gentler cycles rather than making one last forever. Keeping a clean air filter and a tuned furnace prevents the short-cycling that racks up ignition cycles and burns igniters out fast. During any service, the igniter should be handled only by its ceramic base, never the element, since skin oil bakes into a weak spot that cracks on the next firing. Many owners keep a spare $15–70 igniter on the shelf, because these nearly always fail on the coldest night. If yours will not glow, the not-glowing troubleshooting guide walks the checks, a confident DIYer can follow how to replace a furnace igniter, and what a furnace igniter is covers the part in full.
What it costs to replace: plan on $150–350 installed ($15–70 for the part). Replacing on your own schedule, before it fails, is almost always cheaper than the emergency version. The home maintenance cost calculator helps you set the money aside before it comes due.
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Track your home's systems, free for 30 daysFrequently asked questions
Can I replace a furnace igniter myself?
Many homeowners can. It is a moderate DIY job: cut power to the furnace, unplug the old igniter, and mount the new one, holding it only by the ceramic base so skin oil never touches the element. The part costs $15–70; match the wattage and style to your furnace. If you are not comfortable around the gas train or the wiring, a technician will do it for $150–350. A step-by-step is in how to replace a furnace igniter.
How do I know if it is the igniter or something else?
The tell is a furnace whose blower runs and gas valve opens, but that never lights, often locking out after three tries. Pull the burner cover and watch on a call for heat: a good igniter glows bright orange within seconds. No glow, or a visible crack in the element, points to the igniter. If it glows but the burners still will not stay lit, suspect the flame sensor or the gas supply instead. The not-glowing troubleshooting guide walks each check.
Why do furnace igniters fail so often?
Because they take a beating every single time the furnace lights. A hot-surface igniter heats from room temperature to over 2,000 degrees in seconds, then cools right back down, and that thermal shock slowly fatigues the brittle ceramic until it cracks. The older silicon-carbide type is especially fragile; silicon-nitride holds up better. Anything that makes the furnace cycle more often, like a dirty filter or an oversized unit, multiplies those ignition cycles and burns igniters out faster.
Should I keep a spare furnace igniter on hand?
It is smart, and cheap insurance. Igniters almost always fail on the coldest nights, when the furnace cycles hardest and every heating contractor is booked. A spare $15–70 igniter in a drawer means a ten-minute fix instead of a cold weekend waiting on a service call. Buy the exact match for your furnace model now, while you can read the part number off the old one. For the replacement interval and what to buy, see how often to replace a furnace igniter.