MEDIUM URGENCY

Trane Furnace 2 Flashes — Lockout on Retries

2 flashes

Locked out after exhausting ignition retry attempts.

Brand: Trane (Also covers American Standard) | Equipment: Gas Furnace

What This Code Means

2 LED flashes on a Trane or American Standard furnace means the control attempted ignition multiple times and failed each cycle, entering lockout.

Likely Causes (Ranked)

Most common

Dirty flame sensor

What: Coated sensor doesn't detect flame; control assumes ignition failed.

How to check: Pull sensor and check for soot.

Fix: Clean with fine emery cloth.

Shop parts

Common

Failed igniter

What: Igniter doesn't reach ignition temperature.

How to check: Watch for orange glow on heat call.

Fix: Replace igniter.

Shop parts

Common

Gas supply issue

What: Closed valve or low pressure prevents flame.

How to check: Verify valve open; test other gas appliances.

Fix: Open valve or call gas utility.

Diagnostic Steps

Cut power 60s to clear lockout
Watch heat cycle
Clean flame sensor if flame fails quickly
Replace igniter if no glow
Verify gas supply

Frequently Asked Questions

What causes Trane 2 flashes?

Repeated ignition failures. Most commonly a dirty flame sensor or failed igniter.

Same on American Standard?

Yes — American Standard is Trane's sister brand using identical controls.

How to reset Trane 2 flashes?

Cut power for 60 seconds. Fix the underlying issue or it returns.

Related Trane Codes

Related Symptoms

Need More Help?

Try our interactive symptom diagnostic tool or browse Trane parts.

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