Trane Furnace Code E2.1
Hard lockout
Retry exceeded. The furnace tried to light and never proved a flame, so the control has locked out for one hour.
Manual wording: “Retry Exceeded (Flame never sensed, one hour lockout after 3 times)”
Documented for: S8B1, S8V2, S9V2 and S9V2-VS furnaces with the seven-segment IFC display
Likely causes, most common first
- Flame never sensed on repeated ignition attempts
- No gas or interrupted gas supply
- Failed igniter
- Dirty or failed flame sensor
What you can safely check yourself
- Check that other gas appliances in the house work, which tells you gas is reaching the home
- Check that the manual gas shutoff at the furnace has not been left closed after service
- Reset once by turning the furnace switch off and back on
When to call a technician
If the furnace locks out again, stop resetting it. Repeated failure to light needs a technician to check the igniter, flame sensor, gas valve, and gas pressure.
A Trane furnace throwing this code repeatedly has a reason — clearing the code without fixing the cause just hides it.
Sources
- Installer's Guide - Upflow/Downflow/Horizontal Left/Right Gas-Fired, Single Stage Induced Draft Furnaces with High Efficiency Motor (18-CE09D1-1E-EN) (Trane, S8B1A026M2PSAB through S8B1D120M5PSAB single-stage 80% induced draft furnaces) · checked 2026-08-25
- Installer's Guide - Upflow/Horizontal and Downflow Gas-Fired, Direct/Non-Direct Vent, 2-Stage Condensing Variable Speed Furnaces (18-CE01D1-1E-EN) (Trane, S9V2B040U3PSAA through S9V2D120D5PSAA two-stage condensing variable-speed furnaces) · checked 2026-08-25
- Installation, Operation, and Maintenance - Gas-Fired 2-Stage Condensing Variable Speed Furnaces with Variable Speed Draft Inducer (FNR-SVX001B-EN) (Trane, S9V2B040U3VSBB through S9V2D120D5VSBB (S9V2-VS) two-stage condensing variable-speed furnaces) · checked 2026-08-25
- Installation, Operation, and Maintenance - Link Communicating or 24 Volt Gas-Fired 2 Stage Induced Draft Furnaces with Variable Speed Motor (FNR-SVX003A-EN) (Trane, S8V2A040M3PCB through S8V2D120M5PCB two-stage 80% induced draft furnaces (communicating or 24V)) · checked 2026-08-25