What does Trane Furnace Igniter Not Working - Causes & Fix mean?

Usually a cracked or failed hot-surface igniter. Less often, bad wiring, a faulty control board, or a gas valve issue prevents ignition.

How do I fix Trane Furnace Igniter Not Working - Causes & Fix?

Follow the step-by-step diagnosis below. The most likely fix is identified by checking power, sensor resistance, and control-board signals in order — using a multimeter and the part numbers documented in the parts reference table.

Can I keep running the equipment with this fault active?

Generally no. Faults on Hvac units are emitted when a sensor, safety, or control circuit is outside its operating envelope. Running through an active fault risks compressor, heater, or control-board damage. Diagnose and clear the fault first.

What part is most commonly replaced for Trane Furnace Igniter Not Working - Causes & Fix?

The most frequently replaced parts for Trane Furnace Igniter Not Working - Causes & Fix are listed in the Parts Reference section of this guide with OEM part numbers and typical price ranges. Check the table for direct replacements.

Is Trane Furnace Igniter Not Working - Causes & Fix a DIY repair or do I need a technician?

Sensor swaps, fan motor replacements, and condenser cleaning are typical DIY-level repairs. Anything involving refrigerant, gas, or high-voltage (>240V) work requires a licensed technician for both safety and code-compliance reasons.

Trane Furnace Igniter Not Working - Causes & Fix

Trane Furnace Igniter Not Working — What’s Happening

When a Trane furnace igniter is not working, the control system has called for heat but the furnace cannot prove ignition. The hot-surface igniter may not be glowing, may not be getting power, may have failed open, or the gas may never light after the ignition attempt. Trane lists a faulty igniter among the most common reasons a furnace will not start.

On Trane and American Standard fault codes, an igniter problem points to either a bad igniter or gas valve. A separate fault category, ignition proving failure or failed to sense flame, means the furnace tried to light but did not detect flame. If the unit uses a hot-surface igniter, the problem is usually an open, cracked, contaminated, or unpowered igniter element. If the unit has a standing pilot, the pilot and gas supply must be checked instead.

Jump to Fix

Most Likely Causes

Failed hot-surface igniter The silicon carbide or silicon nitride element cracks, opens, or fails with age and is the most common single cause.
Loose or broken wiring at the igniter connector Corroded terminals or a disconnected harness between the control board and igniter prevent power from reaching the element.
Control board not sending ignition voltage A board fault can stop the ignition sequence even if the igniter itself is intact.
Gas supply or gas valve issue The igniter may glow but burners will not light if the gas valve fails to open or gas supply is shut off.
Dirty flame sensor causing immediate shutdown The igniter works and burners light briefly, then the furnace shuts down because the sensor cannot prove flame, making it appear the igniter failed.
Restricted airflow or dirty filter triggering lockout Blocked airflow can contribute to furnace shutdown conditions and ignition lockout scenarios.
Pressure switch or venting fault preventing ignition cycle If the pressure switch does not close or venting is blocked, the furnace may lock out before it ever energizes the igniter.

How to Diagnose and Fix

Verify the thermostat is set to heat, the temperature setpoint is above room temperature, and the system is calling for heat.
Check that the furnace has power at the breaker, the furnace door is fully closed, and the door safety switch is engaged.
Read the LED fault code or display on the control board and identify whether the fault is igniter, flame sense, pressure switch, or gas valve related.
Inspect the hot-surface igniter visually for cracks, contamination, broken ceramic, or loose leads, then test for continuity at the connector and verify voltage at the control board harness during a heat call.
Verify the control board is actually sending ignition voltage during the heat cycle by measuring at the igniter terminals when the sequence starts.
Check the gas supply valve is open and confirm the gas valve opens when commanded if the igniter glows but burners do not light.
If flame lights briefly then drops out, inspect and clean the flame sensor rod and verify grounding and flame signal integrity at the board.
Confirm pressure switch operation and venting if the unit never advances to ignition or locks out before the igniter is energized.

Parts You Might Need

Part	Notes
Hot-surface igniter (silicon nitride or silicon carbide)	Amazon \| Match the exact model number and connector type for your Trane furnace.
Flame sensor rod	Amazon \| Replace if cleaning does not restore proper flame signal after ignition.
Gas valve	Amazon \| Required if the valve does not open when commanded or shows electrical fault.

If your appliance also shows a code on the display, these match this problem:

When to Call a Pro

Call a qualified HVAC technician for any work involving the igniter circuit, gas valve, or burner assembly. Gas furnace ignition and combustion diagnostics require specific voltage, continuity, and gas pressure measurements that must match your exact furnace model’s specifications. A technician will also verify proper venting, pressure switch operation, and flame sensing to prevent unsafe conditions or repeat failures. If you are not trained in gas appliance repair, do not attempt to replace the igniter, gas valve, or control board yourself. For gas line, burner, or igniter work, or if you ever smell gas, stop and call a licensed technician.