HVACopediaTrane · Furnace
Continuous OFF Check power
What the control is telling you
Control shows no light; power to the control is missing.
Applies to: Integrated furnace control
Likely causes
- No power to the control
Test and repair steps
- Check power supply to the furnace.
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
Other codes on the same units
- 5 Flashes Flame sensed with no flame expected
- 6 Flashes 115 V AC power reversed or poor grounding
- 7 Flashes Gas valve circuit error
- 8 Flashes Low flame sense signal
- 9 Flashes Ignitor circuit or neutral-to-common voltage
- Continuous ON Replace integrated furnace control
- Flashing Fast Normal - call for heat
- Flashing Slow Normal - no call for heat
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Source: Trane installer's manual (AUH1B040A9241A), 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.