HVACopediaTrane · Furnace
LED continuous ON IFC board fault - replace control
What the control is telling you
A steady LED means the control has failed internally. The manual says to replace the IFC.
Applies to: *UH1B040A9241A, *UH1B060A9361A, *UH1B080A9421B, *UH1C080A9601A, *UH1C100A9481A, *UH1D100A9601A, *UH1D120A9601A, *DH1B040A9241A, *DH1B065A9421A, *DH1C085A9481A, *DH1D110A9601A
Likely causes
- Failed integrated furnace control
Test and repair steps
- Turn off power at the disconnect before touching wiring or components.
- Replace the integrated furnace control.
Settings for these units
- Clearance to combustibles · Trane S8V2
- Return filter size by cabinet width · Trane S8V2
- Return filter size by cabinet width · Trane S8B1, Trane S8X1, Trane S8X2
- Return filter size - upflow and downflow · Trane S9X1, Trane S9X2, Trane S9B1
- Clearance to combustibles · Trane S9X1, Trane S9X2, Trane S9B1
- Return filter size - upflow and downflow · Trane S9V2
Models that show this code
16 models in UH1, UH1/DH1
Other codes on the same units
- LED continuous OFF No power to control
- LED flashing fast Normal - call for heat
- LED flashing slow Normal - no call for heat
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Source: Trane 18-CD29D1-11 Installer's Guide, Table 21 Integrated Furnace Control Error Flash Codes p.39. Summarized in our own words; check the original manual for your model.
Homeowner looking at this code? See what it means for you and when to call a technician.
For licensed technicians. Gas, electrical and refrigerant work must be done by a qualified, licensed person. Shut off power and gas before servicing, never bypass a safety control, and follow the manufacturer’s manual for the exact model; it and local codes always take priority. HVACopedia is not affiliated with any manufacturer; brand and model names only identify the equipment.