What happens when excessive heat affects the thermal discharge indicator?

When excessive heat impacts the thermal discharge indicator, it triggers the mechanism to eject a red disk. This ejection serves as a visual indicator that the contents of the fire suppression system have been released or "dumped." The red disk is crucial for personnel to assess the status of the fire protection system quickly. This visual cue alerts maintenance crews and flight crews to the need for immediate attention to the system, ensuring that any necessary follow-up actions, such as inspection or refilling of the suppression system, can be taken promptly. The mechanism is designed as a safety feature to ensure that both the flight crew and maintenance personnel are fully aware of the system's functionality and readiness.