Trane Furnace Error Code 1 GREEN / 1 AMBER

The 1 GREEN / 1 AMBER LED pattern on a Trane furnace indicates that the thermostat is sending a first-stage call for heat to the furnace control board. This is a normal operational status, not a fault code. It simply confirms the furnace has received the demand signal and should be working through its startup sequence to produce heat.

By itself, this indicator is not a safety concern. It is a normal status display showing the furnace has received a heat call. However, if the furnace is attempting to start repeatedly without producing heat, you should investigate further or call a technician, as repeated failed ignition attempts can indicate a gas supply or ignition system issue that should be addressed promptly.

If the issue is a wiring connection, repair costs are typically in the range of $75 to $200 for a service call and labor. If a component such as a pressure switch, igniter, or control board is at fault, parts and labor combined can range from $150 to $600 or more depending on the specific failed component and local labor rates.

If the furnace is heating normally, no fix is needed since this is a standard operational indicator. If the furnace is not producing heat while showing this code, check that the inducer motor is running, that pressure switches are closing, and that the igniter is functioning. Wait to see if an additional fault code appears after a failed startup attempt, as that secondary code will point to the specific failed component.

Because this is a normal operational status rather than a fault code, resetting the furnace will not permanently clear it. The indicator will reappear any time the thermostat sends a first-stage heat call, which is the intended behavior. Resetting may briefly interrupt the display but the code will return as soon as the thermostat calls for heat again.