Heating

Ignitor

An ignitor lights the gas burner in a furnace.

What Ignitor means at home

Most newer furnaces use a hot surface ignitor or spark ignition instead of a standing pilot. The ignitor must work at the right time in the startup sequence for the gas burners to light safely. Ignitor symptoms can overlap with flame sensor, gas valve, pressure switch, and control board issues, so the sequence should be tested before replacing parts — covered in a thorough furnace maintenance or no-heat service call.

What it connects to

Parent system

the furnace ignition system

Ignitor is part of the furnace ignition system. That tells you which side of the system a technician will usually test first.

Related components

gas valve, burners, flame sensor, control board

These are the parts most likely to be checked with ignitor. One weak part can make a nearby part look guilty, especially when airflow, water, heat, or controls are involved.

Connected problems

furnace will not light, repeated clicking, no heat, short starts

This is what you are likely to notice at home: furnace will not light, repeated clicking, no heat, short starts. Those clues are more useful than guessing at the failed part.

Maintenance relevance

ignition testing, burner inspection, safety checks, annual tune-ups

This is where ignition testing, burner inspection, safety checks, annual tune-ups matters. The goal is to catch dirt, water, electrical weakness, or airflow strain before the next hard-weather day.

When to call a technician

the furnace tries to start but never lights or shuts down quickly after ignition

Schedule service when the furnace tries to start but never lights or shuts down quickly after ignition. At that point the issue usually needs measurements, not another thermostat setting change.

Use the term in a real decision

Questions homeowners ask about Ignitor

What does ignitor mean in HVAC?

An ignitor lights the gas burner in a furnace.

Can a homeowner fix a ignitor problem?

You can check the thermostat, replace a dirty filter, make sure vents are open, and look for water or ice. Stop before sealed panels, wiring, refrigerant, gas, combustion parts, or safety controls.

When should I call about ignitor?

Call when the problem changes comfort, airflow, safety, water, ice, odor, noise, breakers, or how often the system starts and stops. Tell the technician what changed before you try to name the part.

Need help with Ignitor?

Tell us what changed in the home and where this term appeared. The symptom and the system together are more useful than the part name alone.