Trane Error Code 8: Low Flame Signal

Severity
Warning
Type
led blink count
Where to look
sight glass
Estimated repair cost: $100 — $250 (parts + labor)
Warning: Your Trane HVAC system has detected a low flame signal, which could lead to system failure or safety issues. Turn off the system and call a professional for repair.

LED Blink Pattern

How to Fix Trane Code 8

  1. Step 1: Turn off your Trane HVAC system at the thermostat and the main gas valve.
  2. Step 2: Do not attempt to open the unit or perform any repairs yourself. This could cause further damage or safety risks.
  3. Step 3: Contact a licensed Trane HVAC technician for a professional diagnosis and repair.

How to Reset Trane Code 8

  1. Turn off the furnace power switch, usually located on or near the unit.
  2. Turn off the circuit breaker for the furnace. Wait 30 seconds.
  3. Restore power at the breaker and flip the furnace switch back on.
  4. Set the thermostat to call for heat. If the error code returns after 2-3 ignition attempts, the fault requires repair.

Resetting clears the code from the display but does not fix the underlying fault. If the code returns after reset, proceed to the diagnostic steps above.

What Does Trane Error Code 8 Mean?

When your Trane HVAC system displays error code 8, it indicates a low flame signal in the burner assembly. This could be due to a faulty igniter, clogged flame sensor, or low gas pressure. The system is designed to protect itself and your safety by shutting down when it detects this issue. It's important not to ignore this error as it could lead to further damage or safety hazards.

Common Causes

  • Faulty igniter
  • Clogged flame sensor
  • Low gas pressure
  • Wiring issues

Diagnostic Steps

If... Check Expected
System is not igniting Igniter resistance with multimeter Less than 10 ohms
Flame sensor is dirty Clean flame sensor with emery cloth Clean sensor
Gas pressure is low Manifold gas pressure with gauge 10-15 inches W.C.

Applicable Trane Models

Recall Notices

Trane/American Standard Gas-Electric Packaged Units Recalled Due to Fire Hazard 25-XXX Active

Issued: July 1, 2025

Affected models: Gas-electric packaged units manufactured Jan 2024 - Mar 2025

Fuel gas valve can open unexpectedly, creating gas leak and fire hazard. Stop using heating mode.

View official notice

Replacement Parts

Part OEM Number Est. Cost Where to Buy
Igniter Trane 120-8160
Flame sensor Trane 120-8170
Gas valve Trane 120-8200

Related Codes on Same Models

Other codes that affect the same Trane model families as 8.

Code Description Severity
2 System Lockout Warning
3 Pressure Switch Error Warning
4 Open Limit Switch Warning
5 Flame Sensed With Gas Off Warning
6 Polarity/Grounding Error Warning
7 Gas Valve Circuit Error Warning
9 Igniter Problem Warning
FAST-FLASH Active Call for Heat Warning
SLOW-FLASH Normal Operation (Standby) Warning
STEADY-OFF No Power Warning