The AW-CTD321 conventional rate of rise heat detector uses thermal component to detect the temperature changing in the environment. It can enable fire alarm when the temperature difference achieved the setting rate of rise temperature value or/and the temperature achieved fix temperature. This detector is designed to provide open area protection and to be used with the AW-CFP2166 conventional fire alarm panel. The detector that initiated the alarm condition will have its red LED latched until reset by panel.