Furnace part
Hot-surface ignitor
The hot-surface ignitor is the ceramic heating element that glows to light the gas on modern furnaces, replacing the standing pilot. It heats on every heating cycle and is a wear item: cracks, electrical failure and contamination end its life, usually showing up as an ignition code.
When the furnace control has proven draft, it energizes the ignitor for a timed window (Carrier documents roughly 15 seconds on its current controls), then opens the gas valve. The ignitor must reach ignition temperature inside that window or the trial fails.
Ignitors are brittle ceramic (silicon nitride or silicon carbide). They are handled carefully, never touched with bare fingers, and replaced when cracked, contaminated or open-circuit. A furnace that lights only on the second or third attempt often has a marginal ignitor.
Safety
The ignitor sits inside the burner compartment of a gas appliance. Testing and replacement are technician work; never bypass the ignition sequence or hold the gas valve open manually.
Signs this part is involved
- No heat with an ignition or lockout code after the control's trials
- Furnace lights only after several attempts, or only sometimes
- Visible crack or chip on the element when inspected (look, don't touch)
- Glow that is uneven or does not reach full brightness
Related fault codes
- Carrier 59TP6C status code 13: limit lockout or ignition lockout
- Carrier 59TP6C status code 34: flame lost after ignition
- Carrier 59SC6A status code 34: ignition fault or flame loss
Codes are documented per controller; check the model number on your rating plate before comparing. Not sure which control you have?
Related
Questions people ask
How long do hot-surface ignitors last?
They are a wear item without a guaranteed life. Many last a decade or more; cycles, voltage quality and handling decide the rest. They are inexpensive relative to the service call.
Can I clean an ignitor?
No. Cleaning or touching the element can damage it. A contaminated or cracked ignitor is replaced.
Not sure whether the hot-surface ignitor is your problem?
BC Wide diagnoses by testing, not by part swapping. Tell us the model number from the rating plate and what the furnace is doing.