What symbol typically indicates a warning condition when monitoring a gas furnace?

The indication of a warning condition when monitoring a gas furnace is often represented by a blinking LED light on the control board. This flashing light serves as a diagnostic tool, providing specific codes that reflect the status of the furnace and inform technicians about potential issues that need to be addressed. By interpreting the pattern of the blink codes, a technician can determine the nature of the problem, whether it be related to ignition failures, overheating, or other operational anomalies, which facilitates troubleshooting and repairs.

In contrast, a solid green LED light typically signals that the furnace is operating normally, indicating that no issues are detected. A constant buzzing sound may suggest that there is an active alert or operational status, but it does not provide the specific diagnostic information that a blinking LED does. Lastly, a red flashing warning sign may indeed be used in certain systems or devices to indicate a fault, but in the context of monitoring gas furnaces, it is the blinking LED light on the control board that is the most common and recognized method of indicating warning conditions.