Trane furnace codes
A furnace reports faults on a small status LED on the control board, seen through the sight glass in the blower door, or on a two-digit display. Watch a full cycle of the pattern and count the flashes, including the pause between groups, before you decide what you saw. The code chart is on the label inside the blower door.
Models covered: UH1B040A9241C, DH1B040A9241C.
All 10 codes
Continuous OffNo power to the control (LED off) (pro repair)Continuous OnControl failure: replace IFC (LED steady on) (pro repair)2 FlashesSystem lockout (retries or recycles exceeded) (pro repair)3 FlashesDraft pressure error (pro repair)4 FlashesOpen high limit device (pro repair)5 FlashesFlame sensed when no flame should be present (pro repair)6 Flashes115 volt power reversed or poor grounding (pro repair)7 FlashesGas valve circuit error (pro repair)8 FlashesLow flame sense signal (pro repair)9 FlashesCheck igniter circuit and line N to 24 VAC common voltage (pro repair)
About Trane codes
This page lists the fault codes this brand documents, with likely causes and a short repair path. The codes apply to model numbers such as UH1B040A9241C and DH1B040A9241C; check the label on your unit to confirm yours.