Run capacitor
Common no-start and weak-compressor failure point. Match the microfarad and voltage rating.
Trane 6 Flashes Error Code — What It Means
Six LED flashes on a Trane furnace control board indicates the rollout switch has tripped. The rollout switch is a thermal safety device mounted on or near the burner assembly. It opens if flame rolls out of the heat exchanger — typically caused by a blocked flue, a cracked heat exchanger, a restricted combustion air path, or an induced draft motor that can’t maintain proper draft. A tripped rollout switch is a serious safety event and should not be ignored or bypassed.
Common Causes
- Blocked or restricted flue — Bird nests, ice dams, collapsed vent pipe, or debris in the flue pipe create back pressure that pushes flame out of the heat exchanger opening, tripping the rollout switch.
- Failed or weak induced draft motor — If the inducer can’t pull adequate combustion gases through the heat exchanger, pressure reverses and combustion gases roll out toward the rollout switch.
- Cracked heat exchanger — A crack in the heat exchanger disrupts normal flame containment and can cause rollout conditions. This is a critical safety issue requiring immediate furnace shutdown.
- Oversized burner flame or bad gas valve — A gas valve passing too much gas produces an oversized flame that overruns the heat exchanger opening and contacts the rollout switch.
Step-by-Step Fix
- Do not bypass the rollout switch — The rollout switch is a one-time (or auto-reset) safety device. Bridging it eliminates a critical carbon monoxide and fire protection. Treat the trip as a real event and find the cause.
- Inspect and clear the flue path — Disconnect the flue pipe at the furnace and inspect for blockages from the furnace to the termination point. Clear any debris, ice, or nesting material.
- Check the induced draft inducer — Start the furnace and verify the inducer spins up quickly and runs at full speed. A laboring or slow inducer will fail to maintain draft. Check amp draw against nameplate.
- Reset the rollout switch — If the switch is a manual-reset type, locate it on the burner box (typically a red or white button). Allow the switch to cool completely, then press the reset button firmly.
- Inspect heat exchanger visually — With the burner off and panels removed, use a flashlight and mirror to inspect the heat exchanger for cracks, holes, or deformation. If cracks are found, shut the furnace down.
Parts Often Needed
| Part | Notes |
|---|---|
| Rollout switch (manual reset) | Match the correct temperature rating for your model |
| Induced draft motor | Replace if running slow, noisy, or failing to start |
| Flue vent pipe section | Replace collapsed or damaged vent segments |
Technician Tips
Trane furnaces typically flash error codes through the LED on the integrated furnace control (IFC) board. Code 11 (no previous code) is the startup default — if you see this with a no-heat call, check for power at the IFC. Code 12 means blower on after power-up — normal after a reset. Code 13 means limit switch fault — this is often a dirty filter or restricted return. Code 14 means ignition failure — check gas pressure before condemning the igniter. Trane uses silicon nitride igniters that last longer than standard carbides but are more fragile during handling.
Estimated repair time: Most Trane ignition faults take 30-45 minutes to diagnose and fix. Limit switch and blower motor issues run 1-2 hours.
Need Replacement Parts?
Before ordering, match the HVAC part to the model number, electrical rating, and failure symptom. Check current prices on Amazon - prices and availability change frequently.
When to Call a Pro
A tripped rollout switch that cannot be attributed to a blocked flue is a strong indicator of a cracked heat exchanger — a condition that poses carbon monoxide risk. Do not operate the furnace until a licensed technician performs a full heat exchanger inspection.